Depends what you mean by rich, and what you mean by MTG. There are so many ways to play the game, many of them without spending too much.
For example, my friends and I play Pauper [0]. A format where only common cards are allowed. You can get a strong on-meta deck for between USD24-USD90. It has a huge card pool going almost back to the beginning, so you can build really nice decks!
Even in USD1000 formats like Modern or Pioneer. There are "cheaper" decks like 8-Whack, or Mono-blue Tempo respectively. I think around USD100.
For example, my friends and I play Pauper [0]. A format where only common cards are allowed. You can get a strong on-meta deck for between USD24-USD90. It has a huge card pool going almost back to the beginning, so you can build really nice decks!
Even in USD1000 formats like Modern or Pioneer. There are "cheaper" decks like 8-Whack, or Mono-blue Tempo respectively. I think around USD100.
[0]https://www.mtggoldfish.com/metagame/pauper#paper