restore from time machine

I finally upgraded to a 2019 MBP from my old 2011. I did a time machine restore from my external drive at startup which took about 4 hours. When it was done, I seemingly had all my files but none of my 3rd party software. It didn't even install Chrome. After a quick google search I used migration assistant and unchecked documents & data to get the rest of the software off the external drive. I still had to reinstall some of my audio software. Later I went into pictures folder and there's nothing there. Migration assistant again, from the old laptop. I must've checked the wrong boxes because now the new MBP has 2 users, with mostly duplicate data. This is super frustrating. I thought time machine backups were supposed to be a mirror image of my old laptop. If I were doing this because my old laptop was stolen I'd be screwed.

Now how do I delete one of the users. I can only assume the disk has a partition now. Need to undo that do. Should I try to wipe this machine and start over? Any help would be greatly appreciated.