I always found it odd that one "needed" a large amount of software (Windows, IDE) to program something so small.

Additionally, the IDE is often under the control of the manufacturer. I understand there are good reasons why this means there will be "bloat". Manfacturers are acting sensibly in their own self-interest.

As a hobbyist, I prefer chips that I can program using a UNIX-like OS that I can compile from source.

I prefer to program from VGA textmode, i.e., no GUI. I am not going to run Windows just to program a tiny microcontroller.

I am grateful for projects such as avr-gcc.

IIRC the avrasm2.exe assembler, when plucked from an Atmel Studio installation, also works surprisingly well being run via WINE on Unix.

I heartily recommend PlatformIO. It makes hardware programming much, much easier by handling dependencies, compilation, etc.

"Handling" dependencies automatically is fantastic when it works. But it reaches varying degrees of anarchy and hopelessness when it doesn't.

The more ambitious the framework, the more you have to wade through to figure out what it's actually doing when something breaks...I'd much rather have to deal with some cross-compilation headaches and dependencies than to be at a dead end when the 'black magic' stops working.

Or, I assume, when the company behind the service goes out of business or shifts focus...

That is a risk when you use any service, even if it is open source.

What kind of dependencies are we talking about? Compiler, BSP, peripherals?

Libraries, mostly:

https://platformio.org/lib

And yes, it handles compilation/flashing/etc automatically.

Yes, but there is less install with the IDE