That is interesting!
Sometimes I can hear bits that sound similar. Because all (western) music is made up of just 7 notes that is not all that surprising.

Starting to wonder if maybe what I'm hearing is the tonal center

There are certainly things that have a characteristic sound and that are very common, and once you hear them, you hear them everywhere. I-IV-V progressions are very common, for instance -- perhaps you were kind of taking them for granted before, but now you hear those similarities. Taylor Smith is known for recycling a particular chord progress, but so do blues and blues-rock musicians, for that matter (the ubiquitous 12-bar blues). Or, as another example, introducing the flatted 6th in an otherwise major key -- often by moving from the IV chord to the iv chord -- is pretty common and has a distinctive sound.

I wanted to put an update this for anyone still curious. So it seems it has been a music quality issue. I noticed when using the really expensive BOSE noise cancelling over-ear headphones that sounds as beautiful and brilliant as ever.
Outside of that when I'm hearing recorded music in public on regular speakers or car speakers it sounds weird to me. Easier to hear the separate instruments and notes but it all sounds like it's on one constant lo-fi DJ mix. It's a little upsetting, but at least i have the headphones.
If anyone has had a similar experience in ear training, please share

I guess maybe your ear is getting more diserning as it gets more focused - I don't have perfect pitch but I have heard that if you do it can be difficult to listen to music that is out of tune - maybe it's something similar to this?!

I wondered that too. I'll have to search around for some tests

SINGER

I feel bad for singers all over the world if this is the consequence