that said, why they insist on turning it off, rather than just use ASPs, is a bit unfriendly. but it's definitely not because they are treating you as a child.
You also aren't being denied the capability. There are seemingly innumerable mail hosting services that will let you do IMAP with normal password. You can also host it yourself, using gmail as relay service if you desire.
I'm not saying it's perfect, but it's what I've used to read and write email every day for the last year or two, so it's past that point.
Patches welcome. :-)
fastmail.fm seems well regarded. (it's not on the first page of results above)
Fastmail's most expensive plan offers 100GB, and most alternative providers seem to max out in this range (or lower). Mailbox.org is the only thing that I've found that is (or at least claims to be) privacy-respecting that offers lots of space.
On a side note, given some of the anti-privacy and anti-encryption legislation passed in Australia in the last couple years, I'm not sure Fastmail would be my first choice to replace Google.
Gmail reports a combined storage with Drive etc., so you may find not all of your quota use is actually email.