I have no doubt some people are cheating, but it's totally possible to improve your English skills in 8 years.
How is it cheating to use tools to improve your written English?
I was thinking a bit broader: a change in language (skills) often indicates a bought/hacked account. Chatbots are the latest addition to the list, but I wouldn't worry about spell checkers.
Even to translate directly from your mother tongue.
It depends: if a Newbie has a tech question but doesn't speak English, online translation can help him post and get a solution. But if someone who doesn't speak English is posting large amounts of translated posts, he'll probably end up on my ignore list.