I'll bite.

They're allowed to stop publishing new work whenever they want to. That's part of the free, open-source software game, wherein: We're all free to provide as much as we wish, and also free to consume as much as we want. Nobody necessarily owes anyone else anything and it's really very beautiful in these ways. This is enabled in large part due to the very low cost of distributing copies of intangible software (which can be very close to zero).

But when money gets involved, then things become different. Contracts can be had. Support requirements can be determined. If a contract requires 5 years of support, then it can be reasonably expected for support to continue for at least 5 years.

It's OK to want that, and to never use software that doesn't involve money. It's also OK for an author/company/org to not want that, and to never agree to those terms.

These are different goals, but one party doing it one way doesn't detract from another party doing it some other way. It's all OK.