Tbh bloat usually has nothing to do with tracking or something. Additional code is actually super light-weight. To add full tracking and stuff, we might be looking at a few 100kb additional size.

Using fat frameworks like react native adds much more size. Maybe another 5-10MB.

But what really takes a lot of space is animations, images, background images and stuff like that. A high-res image might take multiple MB on it's own. Multiple of them will take much more.

Edit: I just downloaded and unpacked the newest thread's version's APK and unpacked it.

It has an upacked size of 143MB, of which 83.7MB are assets.

The compiled code including framework and all is 56.9MB. The rest (2.4MB) are metadata.

Mastodon has an uncompressed size of 4.3MB of which 2.4MB are code.