As an Estonian, anything below 80°C is considered a "kids sauna". 80°C - 90°C is a cold-but-workable sauna and proper sauna starts from 90+°C. I'd assume it's the same in Finland as we share a lot of the sauna culture.
This would be same in Germany and eastern european countries too. But it really depend on humidity. High humidity saunas don't have to be hot and get tough pretty quicky. 100c dry sauna is lot more manageable than 60c humid sauna (atleast to me).
Indeed, humidity matters a lot. Most our saunas here are löyly (in Finnish) saunas, so you get a rollercoaster of dry - humid - dry cycles. Once you get to 100+c and throw a good amount of water on the stones, it can get quite challenging to endure :)
Everybody has their personal preference of course. For me, the sweet spot seems to be a moderately humid sauna at 93c. At that point, the löyly is not too harsh yet but is still hot enough to make you feel alive :)
I also prefer around 90-100c with swings of humidity. I think it's most exciting exactly because you can make it temporarily more intensive with the "humid wave".
It's the most popular type of sauna - "the sauna" for a reason.
Whether sauna is hot or not depends on whether you enjoy the cold water plunge afterwards :)
The typical preset on dry saunas in Bay Area is ~165 F (73 C). Which is cold. Waste of time and money :). Usually, by closing or pouring cold water on sensor, one can make it to 180-190 F (82-87 C) - this is where you start to feel like you are in sauna, though it takes prolong time to heat you up enough to enjoy the cold plunge. If you're lucky enough, you can get to 200, 210, 220 F (104 C) - this is where you start to feel relaxed like as if the heat is working inside you.
>Are you actually throwing water? Because even with 80 the steam is pretty hot
Of course those numbers would be impossible to enjoy in steam sauna. The only steam sauna that had a wall thermometer that i've visited in recent years was showing 55 C when it already felt pretty well and hot.
Note - steam sauna and "throwing water" are 2 different things. The steam sauna is a machine generating a lot of steam, so the room is close to 100% humidity.
The "throwing water" is like Russian "banya" - it is in-between of dry and steam, though frequently is more close to dry Finnish sauna - wooden walls, stove, etc. where in addition to the heated air, you'd throw a water on the heater/stones thus adding a hit of hot steam to that air (in some "banya" configurations if you happen to be close to and in the immediate path of that steam you can sometimes get light burns).
Just a clarification as it may not be clear from your message. A Finnish ("dry") sauna always includes throwing water on the stove, which is called "löyly".
People have different preferences for the warmth of the sauna -- as low as 65°C for some elderly folks, all the way up to 120°C for more hardcore people -- but water is always thrown on the stove. You won't get burns, but it can have a real sting. It's enjoyable, but may feel uncomfortable as a new experience.