The thing all companies need is income. Not just once; its gotta be a constant stream of it.
Players will have 3 responses to Cash shop system (let’s assume permanent cosmetics)
No buy
Buy occasionally (a set for your favorite character, good deals in cs)
Buy constantly
It depends on the game. But I think most people are a type 2, and some are a type 3.
In a game with constant development and maintenance, you’ll need type 3s, or get type 2s to buy more.
A huge free player base is not always important to some games. For those, then subscription is reliable income.
Buy to play works for games that don’t require updates and maintenance. For MMOs, this amounts to a type 2 player and not quite enough sustained income.
Fortunately, development costs don’t look that big. At first glance, it looks like a game from 10 years ago. They probably don’t need a huge number of constantly paying players to survive. Cash shop is probably fine.