On iTerm2 my windows are full-screen, black background, zero border or window decorations. I cycle between windows with cmd-` it switches instantly from one full-screen terminal to the next. It's what to me a console should be.
Every terminal app I've tried on Windows or Linux insists on having a goddamn window border. I don't want even a single pixel of border.
And yes, this is enough to make me a die-hard iTerm2 user.
(users care about little things more than developers sometimes realize)
In KDE, in addition to being able to do this full screen, you can have regular windows without any chrome if you want. You just right click on the window title bar and change settings. You can easily set a rule to do this as well if you'd like.
Xubuntu user here: If I open my xfce4-terminal in fullscreen (F11), there is no border and I can cycle between all open terminal windows with Super+Tab. I can also disable the border in windowed mode, though that also removes the title bar.
I use dwm and of the handful of terminal emulator's I've used, none have a border or window decorations. So I don't think they "insist" on having borders.
I really love the fact that I can change profiles depending on CLI prompts. So, when I SSH into a server the background color of my terminal changes to blue. When I change to root but background changes to white. This, along with banner support, helps me keep track of where I am and what user I'm currently using.
This functionality may be available in other terms, but iTerm just seems to nail pretty much everything in one package. I just wish it was available for Linux.
Most terminal emulators are missing support for splits; moving from iTerm2 was painful for me. Been using terminator and kitty, but I still miss iTerm2 5 years later.
I had the same experience, Apples Terminal.app is a really beautifully built terminal. But newer versions of iTerm2 proved me over, it finally felt as fast or faster than Terminal.app.
What initially invited me to test iTerm2 was the one button quake style scroll-down terminal, but I stayed for the better tab management and much more customizable options.
One thing that irks me about Konsole is that it doesn't rewrap the scrollback when the window is resized. Apparently that will be fixed in Konsole 21.04 though:
There are some useful features (tmux integration), but honestly I agree. I've moved back to Terminal.app entirely myself; though honestly I mostly live in the Terminal panel in VSCode these days anyway
On Linux, I just use whatever ship with the distro Gnome Terminal, Konsole... and they work fine.