I think you're absolutely right morally, but I think you've made a pretty important technical error: they're not abusive because "only one party needs to abide...by the contract", they're abusive because only one party can unilaterally change the deal. The companies that make these "contracts" can actually follow them, but since they can change them at a whim, it only really binds the other party.
My guess is that you would probably get kicked off the service if anyone reads your TOS, so make sure to add onerous cancellation charges due to the user in your updated TOS.
What I really don't understand is how it's supposed to be a fundamental part of contract law that there's a "meeting of the minds" where both parties agree to the same thing, and there are these click-through agreements that nobody reads, and everybody knows that nobody reads them, but they're still enforceable. I get why there needs to be a general presumption that you've actually read a contract that you've signed, otherwise you'd be flooded with people saying "actually I didn't read that" to get out of contracts they don't like anymore. But that presumption doesn't make any sense when one party doesn't read the contract, the other party knows nobody reads it, and everybody knows nobody reads it, but we all just sort of pretend.
It is bi-directionally enforced contract, just not a symmetrically beneficial one.
This is my favorite...how exactly can I monitor compliance? No evidence of non-compliance - get tossed out of court. No court order for discovery - no ability to monitor/gather evidence compliance.
The idea that this is even a potential for mutuallity on a TOS is just farcical.
(Insert about 1000 other examples of very awkward ToS updates)
At which time the company has unilaterally denied my access to something I already paid for without seeking my affirmative consent.
In theory I could stop whatever I'm doing, go email the company a brief to the point letter indicating they've broken their ToS and are unacceptably impairing my ability to use my property under the contract that I did agree to, and giving them an opportunity to amend their problem and give me a rollback path.
Realistically the outcome of this is a brushoff and needing to file a consumer protection complaint or get a lawyer.
If the feature is something like "my car" I can't afford that opportunity cost and am coerced into accepting their contract by the way they presented the amended terms.