There are three kinds of time gating mentioned here and they serve different purposes.

The first kind is what I'll call "timed release" gating (ie. you can't do something before a given date, then it's open for good): as was mentioned, it can be used to block access to parts of a game that haven't been fully developed yet, but knowing they're there serves as a teaser. It can also be in place to prevent content rushing (especially in MMOs) and/or somewhat level the competition field. If you get one fourth of a big raid per week, you'll play for at least a whole month, whereas if you get it all and do it in one week, that's three weeks of your attention dwindling.

The second kind is "forced pacing" (ie. you can't do A more than X times per day/week, and it's the same for everyone): in MMOs, this is necessary to maintain pacing and the stability of the economy. If you know the maximum of token X you can get per week is 1000, then people who don't have as much time to invest won't feel left behind if they can manage to get 800 of them or all 1000 of them. It also means the most hardcore won't be bleeding tokens out of their ears before the first week ends. Likewise with gold rewards, it limits inflation without having to resort to absurdly large money sinks (FF14ARR, I'm looking at you).

The third kind is "pay to play time gating" (same as before, but you can pay to lift the block). That one is there only to make you want to cough up the $$$ to get rid of the blocks. That one can diaf