Flac decoder does not require floating point math since 2005:

https://xiph.org/flac/changelog.html

Come to think of it, that still might have been one of the historic reasons for ALAC's creation. Its development started before.

mp3 doesn't require floating point to decode. In the before times, I used mpg321 on an underpowered system because it used the MAD library to decode with only integers, and was able to play my files at only 80% cpu instead of 95% with a floating point decoder. I seem to recall there being a windows player that was faster than winamp, possible because of integer decoding, might have been K-Jofol

https://www.underbit.com/products/mad/