Even inside a big corporation, even as an employee, it's hard to figure out who to talk to about various issues. So as an outsider, it feels impossible.

For security reasons, corporations don't want staff talking directly with customers. So the corporation is a blackbox with very limited communication abilities; both internal and external. It does a lot of things which affect a lot of people but if you fall through some crack, there's nothing anyone can do about it.

Yes, but other corporations that offer public telecommunications services have tech support, however mediocre, even if you can’t just call and ask to speak to engineering.

As I recall that was even true of the free dialup ISPs (NetZero, Juno, etc.) back in the ‘90s.

It is pretty easy for gmail. There is a known (internal) contact page :)