I feel the same way. It's like we're back to the MS-DOS era where every application had its own interface and you had to learn each application's way of performing tasks. macOS and to a lesser extent Windows prided themselves on consistency across applications. But this required developers to voluntarily conform to those platform's guidelines, and in the case of Windows, the goal of consistency was challenged by (1) Windows' backwards compatibility and (2) Microsoft's own disregard for consistency at times, such as Microsoft Office using its own UI toolkit instead of relying on the UI elements of the version of Windows Office is running on (for example, Office 97 introduced flat toolbars, a different style of menu bar, and the Tahoma font, which deviated from Windows 95/NT 4 and its button-style toolbars and its use of MS Sans Serif); this theme even carried over to Windows NT 3.51 where Office's UI was out of place; see http://toastytech.com/guis/nt351word.png for a screenshot). Contrast that with the Web, where there are no common UI/UX guidelines. Sadly this philosophy has spread to the desktop, where increasingly each application seems to have its own UI/UX without regard for the platform's guidelines.
There is one good thing I could think of about the loss of consistency across applications: the underlying operating system matters less when the application works the same across platforms. Ironically this may help with the adoption of desktop Linux; Chrome, Slack, Zoom, and VSCode generally work the same. To paraphrase, this fulfills Netscape's vision in the mid-1990's of reducing the operating system to a bunch of device drivers.
One would think that Microsoft and Apple don't want Windows and macOS to be reduced to a bunch of device drivers. Then again, perhaps Microsoft's and Apple's business models don't require the long-time maintenance of these desktop-oriented operating systems. Microsoft makes a lot of money from Office and Azure, and Apple makes a lot more money from the iOS platform than from the Mac.
Still, I personally lament the rise and triumph of the siloed app, and the decline of platforms that promoted UI/UX consistency through a set of standard human interface guidelines, and I feel personal computing is generally getting worse instead of better.
I've never seen any consistency MS-DOS, Win9x and WinNT. The worst offender is Microsoft itself with the file-browser, settings and office-suits. They don't maintain and evolve their toolkit, they just add new ones and recommend to use them instead:
Win32: Win32, Windows Forms, WPF, MAUI, UWP, WTL, WinUI, MFC and probably more
Gtk: Gtk+, Gtk2+, Gtk3+, Gtk4
Qt: Qt1, Qt2, Qt3, Qt4, Qt5, Qt6
Gtk and Qt didn't just maintain but provides major upgrades and changes. People complained that Gtk changed stuff, which is unfair. The various feature removals in GNOME3 after the first release provided bigger problems. I'm rather sure the changes between Qt major release also require work from developers. Custom theming is an issue with Gtk but also something I cannot recommend as developer and user. It is complicated on toolkit side and faulty on user side. Qt seems do to better in this regard but the user side problems remain. Apple just says just no to theming at all. I've also never felt the desire to theme Gtk because it looked good by default since Gtk3+ and even backported to some stuff to Gtk2+. There is of Java and Swing, yes, but I'm afraid the first error was including a toolkit into a language library.
With Gtk and their HIG most stuff looks decent and usable. Windows? Nobody cares about the HIG. Micrsoft provides more toolkits than I know. And a lot developers just do whatever they want on Windows. Or worse, they use Electron. Microsoft Teams is the worst "application" in this regard.
The font rendering issue. I recommend ignoring the blaming (users) and ignoring (developers) on both sides and instead reading the details involved. Looks like mostly intended and used during development on HiDPI-Displays and they need people experienced in font drawing matters. Some fixes are landing already. Taking into account how much effort was put in Harfbuzz, Freetype, Pango and Cairo I think they can only learn from this - being more careful and keeping backward compatible solutions alongside until the new stuff is working fine for all.
The big difference is that with any of the Windows toolkits, an application written on their heyday will keep working today, good luck doing the same with any Linux toolkit.
Also only Qt is comparable in the full stack experience offered by Windows frameworks (and MacOS/Android/iOS/...), with the caveat it is anyway cross platform and not Linux specific.
Internal political fights between DevDiv and WinDev.
If you are aware that DevDiv controls managed languages, and WinDev Windows/C++, it becomes quite clear why the back and forth between those UI frameworks, given who happens to be on top on a specific time.
And now there is Azure + WebUIs to add up to those resource fighting, oh well.
There is one good thing I could think of about the loss of consistency across applications: the underlying operating system matters less when the application works the same across platforms. Ironically this may help with the adoption of desktop Linux; Chrome, Slack, Zoom, and VSCode generally work the same. To paraphrase, this fulfills Netscape's vision in the mid-1990's of reducing the operating system to a bunch of device drivers.
One would think that Microsoft and Apple don't want Windows and macOS to be reduced to a bunch of device drivers. Then again, perhaps Microsoft's and Apple's business models don't require the long-time maintenance of these desktop-oriented operating systems. Microsoft makes a lot of money from Office and Azure, and Apple makes a lot more money from the iOS platform than from the Mac.
Still, I personally lament the rise and triumph of the siloed app, and the decline of platforms that promoted UI/UX consistency through a set of standard human interface guidelines, and I feel personal computing is generally getting worse instead of better.