We used to holiday at the south end of the Lake quite often.

The photo that @kiwideb uses on her account is from there:

But Taupo the town/city at the north end would certainly have 5G now. It was very touristy, although not now because the NZ tourism industry is all but over. As may be the NZ economy soon...

That 5G map is out of date - they have snuck it in in lots of places

The whole area is quite high altitude so colder than you might expect from just looking at the map - it's colder than Wellington. One of my favorite places though.