Back when I was younger, my CCG of choice was Decipher's Star Trek. I did play Pokemon quite a bit when it first came out, but petered off around the Neo sets. I do still get the occasional pack, but that's more for the Pins than anything. Still have all my cards for them, which would be around 13-15,000 cards across all my collections.
Nowadays, probably the biggest collectible game I'm still into is Star Wars Miniatures. While the game officially ended years ago, it still has a dedicated playerbase who release virtual sets to keep the game alive. Beyond that, my gaming group gets our card game fix from the various deck-building games out there (Dominion, DC, Space Dandy, Attack on Titan, Valley of the Kings, etc) as well as Smash Up (not many other card games allow you to have Time-traveling Cyborg Apes vs. Ninja Grandmas). Plenty of good fun with those and nowhere near the strain on the wallet like what Magic or Warhammer would be (more money to purchase video games then).