Agreeing to a definition tends to make discussion easier, but we can't always have it easy. Sometimes its got to be sandpaper and Thal's balls. I agree its their game, but it is only their game from inside the world - there is always the player even in a very immersive game. Devs still rely on the the players interface to their game (as pretty much anything else) since they cannot remove the person from the game, they're quite god like inside but still just men here (not to take devs down a peg or anything).
Minecraft does have minor objectives and tier progress though :P, good place to claim winning by mechanics. Also I would agree with you that arguing its meaning does not do too much - hence why I think people should work with the nature of language and forgive differences in terms so long as meaning is being honestly shared. I may use different words but if you understand me then we have made a success of communication and can take actions from it.
I suppose I just want to take this point (and to argue/politely discuss what we both agree should be less of a big deal* (lol)) since I think language, even though I'm bad at it, is intimate and to argue the definition as wrong can very often be a challenge to that person as a person. If you say it isn't pay to win then you are saying what they consider winning is not winning, their success is not a success. Well clearly that can't be right, right? But as I can clearly see in your argument is that "its not your perspective of p2w, its the devs" which I think is a good start to the conversation that I feel has been missed in a lot of the "no you're wrong, its not p2w, you're not winning". The devs if honest will not bid content that is winning to the content they deem important, but they will sell what they find secondary or peripheral - even if that is primary to you as a player (which is pretty much what you said). That still doesn't take away the players ability to say that is winning to me, this is how I win at this game - because the devs can say "you will feel success when you beat this game (win)" but if the player doesn't experience it have they won? Sure by the devs definition but not by the player's, this may be ok if it was only one player - but if everyone felt this way then the dev would wisely move their opinion to the player's just so they could ensure money.
*that definitions are not a big deal (but honest attempt to communicate through meaning), not saying no one should be dissapointed or love the cash shop, just that it appears there is a focus to argue a definition than accept their meaning in the conversation. SE can bill whatever they want, players can tell them that sucks. ect ect.
I'm trying to say that both views are accurate and both rely on each other (player's generally only effective in mass, and time) but neither are untrue as much as where the power comes from. Devs are the gods of their game only when consumers accept them to be, or some poor summarization like that of what im saying.. lol