Some tyres are quite loose on rims.
Last MTB tyre I changed I deflated and them just held the tyre up with one hand. The sort of punched, moved my arm. Tyre came off justy like that.

Im going to fit BMX tyres to my City folding bike later when the bike defrosts. Hope the tyres are easy to come off those rims. There 3 speed SA hub on Polish alloys. Think there ok