Paid noncompete (gardening leave) is pretty common on Wall Street. It has gotten much more prevalent in the last 5-10 years, with companies ratcheting up the length and enforcing it on lower and lower level employees. Think - IC software engineers working on some random UI with no idea of current positions or trading strategies, making like $300k total being put on a 12 month leave.
The problem even with paid noncompetes is that you are only getting your salary, not bonus and in the roles it is enforced, salary kind of caps out and bonus ends up being 25%.. 50%.. 75%+ of your income.
Some firms have started to enforce garden leaves long enough that you are guaranteed to miss at least one, if not two bonus cycles.
Additionally, your health care coverage is revoked at most of these companies during your gardening leave so you have to decide whether to go without, take COBRA, or hope you are on your spouses plan already.
Finally, the terms of the contract are generally asymmetric. Your employer has the right to waive the garden leave, but you do not. So you don't know if you are getting a few months paid time off until the day you resign. For legal reasons most companies won't make an offer deal with you and give you a deal like "if you can get out of your garden leave at old job and start here earlier, we'll let you take a month off paid by us before you start" as it is solicitation.
That said - 3 month garden leave over the summer is awesome.