Sure are a lot of IFs being argued about here. Currently, the only arguments that hold any real meaning are those that are not based on IFs, which means currently, the 5700 XT is the best buy because it currently doesn't rely on IFs to achieve that.
Currently, the RTX 2060 is the best buy for someone looking to get into entry level ray tracing on a budget because it doesn't rely on IFs to achieve that. Currently, the RTX 2060 is the best buy for someone looking to get the best performance on a budget if their favorite game happens to be on the DLSS 2.0 support list. It currently doesn't rely on IFs to achieve that. An 8% performance uplift with a 5700XT is meaningless if an RTX 2060 gets a 75% performance uplift with DLSS 2.0. At a $20 difference at most, only one of these cards are "future proof".
Now if the IFs materialize 6 months or a year from now, then there might be something to argue about, and the 5700XT might not be the best buy at that time. However, by the time any of those IFs materialize which weighs heavily on enough games to be released that support certain features, there will be new cards out that have replaced both the 5700 XT and the 2060 super, so in all reality, there is no argument, even based on IFs.
One of the arguments presented for AMD card is that they always "aged like fine wine", like the OP put forth here. Now that the table has turned, all of a sudden it's no longer important? There will just be better cards anyway? In any given time, there is ALWAYS the option you can just buy a better card, but that argument is just a diversion here to avoid a 2060 being more future proof than a 5700XT simply because of DLSS 2.0
Hardware Unboxed acknowledged this. Not sure why it is hard for others.
Remind me again why you decided to buy a 2080 Super over a Radeon VII or 5700XT? If you keep your card for 3 years which one do you think will be more prepared to handle future games?