I studied for the interview I wanted (by being a thoughtful software engineer in my day job) and not for the interview they offered (which would require me to either be a professional leetcoder or some algo/performance expert). If they didn’t want a good software engineer then they’d have to pass on me. I made it clear in every session that I was thinking through the problem, asked good questions, and when there were aspects I could write concrete code for I did. If you score by solution competence and performance I think I aced 2 of the coding sessions and did pretty mediocre in the other 2. My interviewers must have been willing to go a bit off of the default mode of operation as I managed to get an offer.

I don’t know if interview performance has anything to do with negotiating power, but I was able to get damn near the highest possible total compensation my level allows for without a competing offer.