Is there anyway to do visual basic, Access-type apps in the cloud? I mean a full cloud-based IDE?

Might not be the exact right feature-set here, but Google Sheets allows you to write custom functions in Javascript. IIRC, you can hook a Google Sheet up to Google Forms and this might give you what you want.

It doesn't let you do declarative queries (read: SQL) and it's not relational.

Google Apps Scripts (equivalent to VBA in Office) can script most Google products; you could build a form on one tab of a Google Sheet, use Apps Scripts to store and query data against Cloud SQL, then use another tab of Sheets to output the data from Cloud SQL.

https://developers.google.com/apps-script/guides/jdbc

That's not what a replacement for Access should be like.

LibreOffice Base is an Access-type program

In the same way a Lada is an automobile.

Perhaps it's improved, but a while ago I tried to program Base and found the documentation around it's functions/methods/properties to be scant and/or terribly out-of-date, and pretty much useless.

Ouch!

:-)

Yeah, it's the unloved step-child of the LibreOffice suite, we fix stuff sometimes, but there is no commercial user of it to fund development

In theory, but not in practice. Yes, it's a somewhat visual database. But it doesn't have anywhere near the power or ease of use that Access did 20 years ago and its integration with the rest of LO isn't even close to what Access does in MS Office. If that weren't bad enough, the underlying database it uses is effectively an island in the larger open source world.

In the Windows world, just about everything can interact with Access. Just about nothing can with Base.