Yeah, just updated to HWINFO 6.42. It does indeed show memory temperatures. Just under GPU Core temp. But only for GDDR6X. It doesn't show GDDR6 temps, maybe not necessary as it doesn't run hot?

Here's mine at 28c ambient:
Asus TUF - 98c
MSI Ventus - 108c (near throttling)
Zotac AMP Holo - 96c
Gainward Phoenix - 86c
Palit GamingPro - 88c

All at +1000 memory except Palit at +700. The Asus, MSI and Zotac are deshrouded, and I have zip tied 120mm/140mm fans.
Surprisingly, the cheapest 3080s on my rig perform the best, and they're not deshrouded. The more expensive brands perform worse, even though they are deshrouded with high quality fans!