Gotta follow through on your threats so he learns to take you seriously & that actions have consequences.
I agree that you have to follow through. However, at this age they don't have the concept of time that we do so gping to soft play the day after ia probably the same as going later. Consequences for toddlers need to be immediate. For example, snatching a toy, now you don't play with it. Also, they normally have meltdowns because they can't control their feelings. This is something to learn but not their fault. Same as pushing boundaries or sharing. They are still little.
I did this today. My son was swearing , hitting , shouting and still expected to go to soft play ... I said absolutely not. In my eyes they need consequences, not everyone may see it that way but i felt his continued difficult behaviour wasn't going to be any better if I took him to do something nice so we simply didn't go🤷🏻♀️ I explained why to him though obviously , this age is so trying 🥲x