No! God no, please no. Rotating formats are the worst, and a huge money grubbing scam.
Power creep is also not a good method, and it does not necessarily have to happen, especially with a digital game where they can adjust both old and new things at their leisure. Releasing new cards, balancing over turned things, buffing older cards, and supporting various archetypes prevents things from getting stale.
Not to mention it divides the player base between formats. Gauntlet is enough of an alternate game mode, although it really ought to be free, but harder to get rewards out of.
A rotated format is not any friendlier to a new player, the costs are usually the same to make a deck, they have to do just as much learning, and the meta Is super stale for a couple months due to the tiny card pool. And then guess what, time to throw away all your old stuff and buy everything new! To prepare for yet another boring stale couple months, and then it repeats again.
Has anyone ever actually been scared away by a large card pool? I see big pool and think lots of customization, I can do what I want and not be all cookie cutter, and am thrilled with the constant discovery. Most of the learning is mechanics and basic tactics which have little to do with the card pool.
There is a reason why Modern and EDH in MTG are quickly becoming more popular than standard despite that Wizards goes out of their way promote Standard. And unlike Legacy/vintage because edh/modern gets the balancing attention they need, they have been very successful, and that balancing is much easier for a digital game to.