EDIT: It seems that while some article say they retroactively apply this other state they expliticly do not do so. Through they seem to have removed previous clauses which would allow developers to stay on the version they started developing with which hadn't had that terms jet. Which is scummy (because it relies on "tricking" companies into those terms) but might be legal.

put new installs are not newly published products, i.e. they don't involve the publisher bundling in a new version of unity they got from the vendor

so while the installs are new the contract between the producer <-> publisher <-> distributor <-> unity is not

which means it's uniliteraly retroactively changing a contract

which sounds like very much not very legal

if you consider that the other contract partner is somewhat dependent on unity (switching is expensive) it might also involve other laws not necessary racketeering but something in that direction

and while unity might be able to terminate the contract with the publisher (by their lawyers sending them a letter, not automatic) this is between the publisher and them i.e. it shouldn't affect already sold products

but they explicitly want additional fees from distributor or publishers for _already sold products they have no control over_ which is just tbh. ridiculous

and even if it only affects newly sold products it's still affecting already produced product retroactively which still is highly questionable

Well if that is the case it is either a) illegal. b) the developper/studios already agreed on a license that would allow unity to change term and licensing fee on stuff made long ago and screw them whenever they want.

If the answer is b, then I guess those involved should just slap themselves and swallow it instead of complaining.