RTX 4080 SUPER adds 0 GB VRAM for +$650 (145% premium). The real question is whether your workflow needs models that RTX 5060 Ti 16GBcan't run.
$ recommend → If you own a RTX 5060 Ti 16GB: wait. Prices drop, refresh cycles continue. If buying new: get the RTX 4080 SUPER IF your budget allows AND you need the extra headroom.