I judge people based on whether they get their point across -- you don't know the age or national origin of the person posting, for all I know I'm speaking to someone much younger than I who speaks more languages than I do.

I do judge spelling errors harshly, since most modern OSes will give a nasty red squiggle.

Anyways "immoral" is such a strong phrasing. Killing someone is immoral.

Letting someone argue their point badly is... well, I was raised Catholic so lets use that lens: Catholicism would refer to it as a "venial sin" -- you won't be going to hell for not correcting someone's grammar on the internet.