Yes, agreed. But neon lamps weren't limited to the Bell System; everybody who worked in electronics at the time used them for something, though not as commonly as things like capacitors and resistors.

Microwave gear of course had to use vacuum tubes until transistors got fast enough; as you say, although you can switch a voice signal with a neon lamp, you can't amplify it that way, and microwaves are a million times faster than voice. (Amplifying voice with a saturable inductor, a so-called "magamp", had its day too, though magamps are rarely seen today outside of ATX power supplies.)

But a lot of electronics didn't have to run at microwave frequencies or even voice frequencies; motor frequencies or powerline frequencies were enough.

Which page are you referring to in [2]?