The second approach is hiring junior/mid level's and mentoring them into the senior roles. It takes a little longer, but the hours of mentoring are a much more effective use of my time than interviewing hundreds of candidates in my experience.
I've been out of the game for 2 years, so I can only imagine with LLM assisted coding my second option would be even faster.
All that's predicated on test driven development to minimise the load on seniors for peer reviews.