No, not at all. Compression reduces the dynamic range. It makes things sound louder because there’s less dynamics in the project. And, yes, this affects LUFS because LUFS is a reasonably good (but not 100% accurate) way to measure “loudness” as humans hear it. But it’s also important over what period of time you are measuring it: instantanuous, averaged out over a short period of time (say, 20 seconds) or averaged out across the whole track.
It’s a bit difficult to explain but maybe this will help:
A track like an Oasis one from WTSMG mastered to -14LUFS might be between -12 and (say) -20LUFS at every point in the track. If you measure the whole track it might be -14LUFS.
An orchestral track with lots of dynamics might be between -8LUFS and -20LUFS across the whole track, and still be -14LUFS overall. The loud parts would be louder than the Oasis track, but the quiet parts would be very quiet, to the point where you might not hear them at all on a typical car stereo whilst driving at 70mph.
Overall the OASIS track will feel louder than the Orchestral track, even though (on average) they were the same level.
So it depends on how you measure these things. Offhand, I’m not sure how Spotify or YouTube do it, and what the impact is, but it’s good to know this so you can make creative decisions about your work and how you want it to be represented on these platforms.
Cheers,
Keith