Do they have the right to do that? Do customers in any country have a right to demand a product's firmware be restored to factory-state (on the grounds that what they received isn't what they were sold)?
I returned a Bose speaker when it stopped letting you cast to it without their app, and have returned my Ring external camera when they removed customisable motion zones (I need to block a specific tree that moves in the wind). Plus more.
I’ve never had a problem doing so, I’m always polite and just explain that it’s no longer as advertised and print out the product update notes showing that they removed/changed x or y feature.