Storage

It depends on the type of game. If it's a simple non-graphically demanding game (sudoku, chess, etc), then it's big.

If it's a graphically demanding game (PUBGM, Apex Legends, MBL), then it's normal.

Up to you, if you need the space and you're ok with not playing the game then you could delete it.

A single App/Game that requires 20GB is very large.

If you are short of available storage space, or if you have an iPad model with only very limited storage capacity (e.g., an iPad model with 32GB or 64GB storage), you may struggle.

Whether or not you need to consider deletion of the App/Game, only you can decide. If you have run-out of available space, then you’ll need to consider deletion of either Apps or data.