I've got a few thousand Magic the gathering cards here, but I quit around the same time they started with mythic cards. The game is certainly fun, interesting and never the same, but man...it's so easy to keep spending money on it.
I stopped regularly buying Magic cards around the time 5th edition came out. They were pumping out new expansions like every 2 months, which isn't horrible in itself, but each expansion at the time was built on cards that could ONLY be countered IF you had that expansion...
An example are the Sliver cards....a type of creature that can ONLY be blocked by other Slivers...so if you didn't have that expansion, then you were likely to be taken out easily by someone using those cards. Now, if there were only a few cards, that'd be one thing..but it seemed like every single critter in that expansion was a Sliver...enough, at least, that you could build a deck with an entire army of the things and not a single non-sliver creature in it.
It's actually kind of funny. We complain about all the microtransactions and minimal content DLC pumped out by game companies these days.... Wizards of the Coast has been doing it for over 2 decades.

At least with a DLC, you know what you're getting....paying $3 for a booster pack may yield you 8 cards you already had or that can't even be used (banned cards)