I still have my tv I have been looking at new ones but really the content is not out yet. So buying a new £2000 to 5000 tv it is not worth it yet. Also with all the fighting between the 4 difference types of HDR it is hard to work out which one tv broadcasts will pick. Samsung will not pay to use dolby vision and will be doing their own updated HDR to complete with it. Also the fight over if OLED vs QLED screens are better it is so hard to pick which one will win out. I spent £2700 on my TV when it came out and like you are so gutted I did. I don't want to make the same mistakes again. I was going to get the Samsung upgrade program but reading all the small print it is also risky and you could end up not getting to upgrade after the two years and be left with a out of date tv and still have another 2 years of payments left to make on an out of date tv again.
In theory the upgrade programme is good idea the same as future proofing a tv with a evolution kit was but things chane so quickly in tech. The money you would pay each month to Samsung could be put in a jar and after two years you could buy a new tv with out being stuck under the dictatorship of the contract you have signed.