>>You don't need to "cram" for something if you understand it well. It's a matter of techniques, not answers.
No, you absolutely do need to cram to get through the interviews. In fact the questions on leetcode are designed for this very purpose. Every question has one common theme. And one 'catch' that you absolutely need to know to solve them.
If you haven't looked at a question in X months chances are you will struggle to solve it quickly even if you have solved it before.
If you are out of a job, just buy leetcode premium. Keep doing it for 15 hours a day. Then start applying for interviews.
Its the dumbest way to hire and get hired.
Not even least surprised people can't hire a person to get a darn thing done.