ToS are the worst thing ever. They are “contracts” that you are required to sign to do literally anything in the world but are not allowed to negotiate and can be modified at any time without your consent and your original signing is propagated to the new contract and it is still considered binding. Also, they are allowed to put clauses in which hand over rights to your property, intellectual or otherwise, which is irrevocable and perpetual. Additionally, you have many “software” providers putting clauses in which state that you only lease the license, you do not own it. Even if you have a physical media with the software, you only purchased a lease and it is therefore illegal for you to resell it. They are also allowed to revoke your lease at anytime, without recompense of any sort. That is the real power of SaaS, not the subscription, but the fact that nobody is ever allowed to own something, no matter how much money you have paid.

Yes, as others have said, they are virtually unenforceable, but it does happen often enough to make sure you are afraid of it.