[OA] OA was fair. Programming part are leetcode easy and easy-mediums, straightforward simulation, backtracking, dfs, strings, etc. No DP/graphs but ymmv.
[Final interview] (Case Study) I think the interviewer came up with their own prompt. It's mostly discussion-based, with a virtual white board. It's not too technical. I'm guessing its testing your communication/logical reasoning than system design skills. (Pair programming) 1 question, same format as the OA on the same platform, leetcode easy.
[Overall] Technical difficulty isn't bad. Interviewers who are current software devs seemed friendly. Had a good experience, yet got rejected.