RTX 5060 Ti 16GB adds 0 GB VRAM for the same price. The real question is whether your workflow needs models that RTX 5070 Tican't run.
$ recommend → If you own a RTX 5070 Ti: wait. Prices drop, refresh cycles continue. If buying new: get the RTX 5060 Ti 16GB IF your budget allows AND you need the extra headroom.