Slow Loading

Try reinstalling, it could be that your drive is failing too. When it does that it has to recover sectors and that takes extra time.

@des1dragon
can you try installing it on another drive and see if it makes a difference? it shouldn't be too slow to load, especially not slower than console in my experience.
mine loads off an internal ssd when i'm playing on pc and it's fairly speedy. when i'm on console it takes much much longer to load (xbox one x), although the series x (a friend i play with has one) seems pretty quick too.

I got an OG XBOX One and a 2:30 second Mermaid is not uncommon.

@des1dragon
it might need a defrag (if it's not an ssd - iirc ssds shouldn't be defragged) then. if an update was added then it's possible that a lot of files were added or changed and written to the end of the harddrive, far away (in terms of reading distance for the drive head) from the other data.
if it's not an ssd try opening windows explorer - go to this pc - right click the drive and select properties. under the tools tab there should be an option to defrag and optimise the drive. if that doesn't make a change after running then try the error checking (in the same place).

Depending on your PC specs it's also possible that, if your HDD is full, that you need to free up some HDD space for virtual memory. If you don't have enough memory then the computer occasionally writes memory down to HDD to free up space for other things (this is virtual memory) but if there's no HDD space then it can start "thrashing" writing memory down and then having to remove it or write it back up and then filling again too quickly and pausing to write down again. this can slow things down a lot too.
Here's some more info on thrashing: https://www.minitool.com/lib/disk-thrashing.html