Good questions. I could argue that the game rules can reasonably include clauses such as, "We can adjust weapon/defense parameters at any time." But the addition of a blocklist feature is a bit harder to hand-wave away because it could be said to be economically damaging to spammers. I would say yes, if the ability to message everybody is advertised as a feature, the company would need to refund the spammers (and kick them off.) Hopefully the company will learn to provide clearer terms of service next time.
In general I think the best answer to your objections is to require companies to specify up front exactly what features are being sold, and for how long they are guaranteed to be available. The onus would then be on the consumer to evaluate the list of guaranteed features against their wants and needs. Consumers would hopefully learn, over time, not to buy products that don't provide these guarantees up front.
Right now what they (we) are learning is not to trust anything with an Internet connection, because of abuses from a small number of prominent bad actors. Which is unfortunate.
In general I think the best answer to your objections is to require companies to specify up front exactly what features are being sold, and for how long they are guaranteed to be available. The onus would then be on the consumer to evaluate the list of guaranteed features against their wants and needs. Consumers would hopefully learn, over time, not to buy products that don't provide these guarantees up front.
Right now what they (we) are learning is not to trust anything with an Internet connection, because of abuses from a small number of prominent bad actors. Which is unfortunate.