Generally, they go hand in hand. You can't be well educated if you are as thick as two short planks.
It is quite easily possible - quality of written English in the context of informal discussion over the internet is not assessed as part of the admissions process of, to my knowledge, any University in this country. Entry is granted based on the accumulation of UCAS Points, which you get for passing A and AS level exams at a secondary school level.
Crap grammar on the internet is generally a sign of laziness and a lack of respect for the medium they are posting in, rather than a lack of intelligence of education on the part of the poster.
If your judge of whether 'anyone can get a degree' is mostly based on the standard of grammar on internet forums, then I think it says a lot for the validity of your opinion.
Uni is NOT a free ride. Many see it as being a dead easy, free ride, where you spend your entire time getting drunk and having a laugh. These people fail their degrees, or they drop out before the end. The few that do pass fall into two categories - those who are incredibly gifted and can thus get a decent mark with little effort, and those who scrape through with a rubbish mark.
Generally speaking, anyone cannot get a degree. Many think anyone can, and many try, but compare admissions against graduate acheiving a 2.1 or higher and I think you'll find the figures are very different.