I wouldn't say that's necessary.

I've been in a senior role for 5 years and I somewhat recently interviewed at Google for an SRE/SW position with basically no prep (did maybe two practice exercises) and passed it no problem. I turned them down for a variety of reasons, but if I were to interview again I might even spend less time practicing.

It's true, however, that at some companies, performance impacts leveling and compensation, so there's surely value in being (possibly even over-) prepared.