If I play chess, and someone changes the rules so pawns can now move in any direction, and rooks can now move diagonally, and kings can now move any number of squares, am I still playing chess?
That said, if you say to the person you are playing against, "But those are just optional rules. You don't HAVE to play it that way. I am, but you don't have to. It's up to you if you want to challenge yourself that way or not."
Do you think the other player is going to not use the new rules when the entire game is now designed around the new rules?
Comparing chess to dnd is apples and oranges. Chess has a set of rules where you HAVE to play that way or else you can't play the game. In DnD the rules are there as a guide. If not a guide and you HAVE to play 5e the way it is, then homebrew rules would not exist.
I am actually not opposed to homebrew rules, believe it or not. What I disapprove of is changing 5e rules to things that don't make sense from a balance and realism standpoint.
For example, I don't have a big problem with them making potions a Bonus action. I'd prefer them to be an Action because once you make them a Bonus then the Rogue's Fast Hands special ability becomes almost pointless. One of the main points of them having that special trait is because Rogues do things faster than most others. Make potions Bonus for everyone and Rogues become less special.
These are the kinds of homebrews that are ruining the game from a balance perspective and making things less special. Food as a healing item ruins the entire point of potions. You can eat them as Bonus, no matter how ridiculously big, and they can heal just as much or more.
They should be items meant for survival, not healing, so that healing potions aren't completely negated.
