Yes, I believe it is pay to win. This isn't something to hide or be ashamed of; Dacon is very explicit about the things he offers on the stores, be it minions, ranks, or keys. Having a high rank, like MVP+ or ELITE, gives a huge amount of perks that would not be available to the average player. Yes, you can save up cubits, but this takes a lot of time and is generally pretty costly as well. Minions, if they behave similarly to Olympus, can make or break a productive island.
Again, not throwing any shade, but I don't think there's any point denying that.