That's what most normal adults would do.Yes, I would upgrade my phone to play this game (although I don't need to because i have a modern mac and iPad pro). But since I'm already an iPhone user and would own one anyway, I would actually rather have invested in a newer iPhone over a whole PS5 i barely use.
I'm on a 13 Pro Max now that is turning 2yo when I renew my contract for a 15 Pro Max. Whether RE4 came out or not I'd still be renewing every 24 months until I die.
So RE4 being available without my needing to buy a gaming PC or console is a bonus.
Apple knows users like me are already replacing their mobile phones on a schedule for nearly 3 decades already. This is not a problem for me or other users with my profile.