The problem with Samsungs is thar once unlocked, you permanently burn the knox security fuse. So, even if you re-lock it, it’s not going to play nice with banking apps. It’s a one-way install only. Also I’m not so sure how LOS plays with banking apps… The only one that allows full re-lock AFAIK is the Pixel (which is what I have now, after nearly a decade on Samsung).
I find the most annoying that gmail will ignore spam tagging of well known emails such as Facebook, Amazon etc and will continue to feed you their crap regardless of your choice.