Unfortunately. they will be no update for the Q90r. its more of a hardware change than a software one so you won't be able to get HDMI 2.1 on the TV. in fact, no 2019 models had HDMI 2.1 except the 8K higher models. if I were you. I would just get a LG CX OLED which is what I did. and 2020 models that have HDMI 2.1 doesn't even work properly with the PS5. It does 4K120 but without HDR. So I would suggest you wait for 2021 Samsung TVs. Or your best option is LG CX with has 4 HDMI 2.1 ports which is good for future proofing.
