I'm not denying the excellent support that Samsung is providing for their phones, but they are making 'guarantees' only for the high-range mobiles.
Their low and mid-range phones are not guaranteed software upgrade support, but may get upgrades if feasible.
Please see below post where they are making the OS upgrade guarantees only for the high-range mobiles. None of the mid-range or low-range phones are in the list.
Select Galaxy users will now enjoy the latest mobile experience for longer with four generations of One UI and Android OS upgrades
news.samsung.com