Prepping for algorithms is somewhat mandatory if you've never encountered those types of questions before, as you'll most likely fail without some familiarity/p

Prepping for algorithms is somewhat mandatory if you've never encountered those types of questions before, as you'll most likely fail without some familiarity/practice. However once you're able to do well enough on them, they're actually the least important for senior engineers. Algorithm questions are mostly just treated as a weeder/low tech bar for senior engineers. Doing well on the behavioral, architecture, and practical interviews is usually much more important for senior candidates.