Well, this us true for only the simple analog circuits. A modern analog front-end of a 5G modem or so is absolutely impossible to understand visually. Even the sub-blocks like the phase-locked-loop (PLL) or the analog-to-digital converter (ADC) are often vay too complex to grasp alone. But with a good hierarchy of the schematic one can divide each of these into sub-blocks and understand each of the sub-blocks. The whole is still too complex to understand fully, even for its designer. This causes a lot of simpe mistakes to happen like forgetting to connrct two nodes and not realizing till the silicon failing after the production...
Yes, but there is a certain magic feeling of power in knowing that you could, with a steady hand and a soldering iron with thin enough tip, meaningfully alter or repurpose the analog parts of the circuit.
It's like the difference between a game whose logic is 90% Lua or Python scripts, included plaintext in the game directory, vs. one that's 100% compiled C++. One is susceptible to modding by a 12 year old kid armed with a notepad, or a 22 year old kid trying to make a flashy visualization of finite state machines to get a good grade on CS labs for little work[0]. The other is... still mutable, if you get into reverse engineering, and probably pay for (or pirate) SoftICE[1]. More importantly, one lets you learn how to make similar things, through looking and experimenting; the other doesn't[2].
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[0] - Well, that involved Processing to show an animated diagram of a simple FSM, and Colobot with a flying Moon robot programmed with that FSM for the flashy vis, plus some half-assed IPC using text files...
[1] - Ghirda wasn't a thing back then.
[2] - See also "Show source" in browsers - used to be a great on-ramp to webdev and programming, back when JS was just a toy language.
