I have more than 20 years of experience and I manage to find time to do leet code exercises before I interview.

I'm saying that testing people for their skill, in any way, will have imperfections and will wind up excluding people. If it excludes people based on something they can control that's probably not the worst thing. Not everybody can get time to practice, but do I really want to be working alongside people who don't practice? Maybe in some jobs I do maybe in some jobs I don't.

If someone really does have 20 years of experience then a single evening of practicing will do a lot more for them than it will a fresh faced kid from college even if that kid from college does it for two or three hours every day for a week.

I just simply don't accept the notion that leet code interviews favor people based on age.