TU104 is also used in 2070 and 2080 cards. It was a big deal when it was brought to 2060 Super because it brought with it a 256bit wide memory bus. But this variant does away with that bus, so it's basically the same as TU106. Since the plain 2060 was the only card using TU106, it has probably become cheaper for Nvidia do away with one SKU and carve both 2060 variants out of the same silicon.
Uhm, RTX 2070 and RTX 2060S are both made from tu106, with chip's full 256bit wide bus enabled.