(With the new plan) If I purchase a 1 year subscription, then I get a perpetual license for the version AT THE TIME OF PURCHASE. Any upgrades I get during the year go away if I don't subscribe for more time.
Here is a link to help you understand: https://sales.jetbrains.com/hc/en-gb/articles/204784622
Yes, the customer doesn't get to keep the latest version if they stop their subscription, but JetBrains needs some reasonable hook to cover support costs, and quite frankly, their software is relatively cheap in the commercial market and generally works as expected.
It also addresses the concerns of those who claim "they'd be willing to pay more". If you decide to stop your update subscription, you have the option of getting a perpetual license for the latest version at that point by simply buying a year's worth of updates.
If there's a better option that keeps JetBrains in business and customers happy, I'm sure many would like to hear it.
People who wanted future improvements would still be incentivized to pay for them, Jetbrains would be incentivized to continue improving the software so that people would want to keep purchasing, and nobody's current working setup would be held hostage at the end of the year!
Otherwise, JetBrains incurs the cost of producing a new version, but then has no revenue stream to support it.
In addition, if you keep upgrading every year, they give you a lower price than you would have gotten before. However, if you don't stay current, then yes, you'll pay more than you used to.
JetBrains hasn't really raised their prices in five years and meanwhile the cost of living has gone up. Things can't be completely in favour of either party; there has to be a meeting in the middle.
For what it's worth, I have no affiliation and I had let my license to IntelliJ lapse so was one of the aggrieved parties when they first announced the new pricing. This announcement however satisfied me enough that I decided to renew.
"You will receive perpetual fallback licenses for every version you’ve paid 12 consecutive months for."
Look at the third example. This seems to be about on par with what is offered now. Depending upon how much their release cycle changes and how many features make it into each major version.
Edit: spelling!