Once upon a time, there were three branches in US electronics - Bell System, IBM, and everybody else. You're reading the Bell System viewpoint.

In the Bell System, most electronic components came in rectangular metal cans, often hermetically sealed, usually labelled "Western Electric NNNN Network". The Bell System loved inductors. Inductors don't wear out. They often used unusual inductors, such as saturable reactors, or inductors with a copper slug. For the same reason, they liked gas-discharge tubes, although they're not suitable for amplifying audio.

IBM liked plug in cards. Some cards in tabulating machines had moving parts connected to drive shafts. Tube computers had plug-in subassemblies.[1] This allowed maintenance of large machines in the field. Thyatrons were used in some early printers, as the drivers for the printer magnets. But not for logic - too slow.[2]

Everybody else had metal chassis with tubes on top and everything else underneath. Military gear would have extra hold-down arrangement for tubes, and often metal tubes, but usually stayed with the metal chassis form factor.

[1] https://www.righto.com/2018/01/examining-1954-ibm-mainframes...

[2] https://bitsavers.trailing-edge.com/pdf/ibm/logic/223-6746-1...

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]?