Yep, known issue, sorry about that: https://www.reddit.com/r/apexlegends/comments/fgr1uq/the_assist_credit_bug_is_worse_than_i_thought_but/fk8b6mu/

Naurloss

Excuse me for question not on topic, but are you aware about loss forgiveness still not applying when game starts with less than 3 people in a squad, or a teammate leaves before his banner pickup time runs out?

Or is it still "working as intended as it was in season 3"?

If you have examples I'd be happy to look into them, as far as I know everything is indeed working as intended. The system for when you get loss forgiveness or not is actually pretty complicated and I don't think we ever fully listed out the conditions anywhere.