Stealthing is wrong.
If someone wants to get fucked with a condom and the top takes off the condom (or the other way round) it is wrong. Especially when the top/bottom knows he has any sort of disease.
Going to a bath house/sauna etc, does not justify stealthing in any way shape or form; the point of an establishment like that is that so for the most part people stay anonymous. The definition of anonymous is; a person not identified by name. Therefore, being in a bath house/sauna does not give ANYONE the right to stealth; even with an infection or with no infection.
If a bottom/top is reckless and does not use a condom for anyone; then stealthing is still wrong if the stealthier knows he is infected but nobody can be blamed apart from the reckless bottom/top.
If you think stealthing with intent to infect someone is not wrong and you are using rubbish arguments such as "suspended morality" then you are tying to jusitfy your own fantasy to make yourself feel like your normal or that your fantasy/actions are justified and sane. You don't get to decide if someone becomes infected with anything; your part of the reason gay sex is such a taboo - it's ruining it for gay/bi/straight people who enjoy it.