I optimized applying for jobs and interviewing out, so I don’t waste time with that. My last interview was in 2003, and that was a formality because the CEO was a former colleague and mentor. I have been working steadily and lucratively since then.
If you want to go through the grind applying for the same jobs as thousands of other people, by all means prep for interviews on leetcode or whatever. That’s an example of Goodhart’s Law, optimizing for the wrong thing. If you want to always have a job make yourself indispensable. Contribute value to the business that you can measure in some way other than git commits. Find jobs through contacts, friends, colleagues, referrals.
Most jobs aren’t advertised. Put another way most companies will hire someone who can add value and solve problems. Be that person.
It’s not managers who created the clown show of tech interviews and Byzantine hiring processes. It’s us, the programmers who did it to ourselves.