It depends on why they are doing it. Mistakes do happen, and it is possible for anyone who does a lot of work to get confused for a brief period. Sometimes, they may revert things back to the first really good answer and then paste in any positive additions after a spate of vandalism. Sometimes the spelling changes are regional in nature, and if someone changes something to International English, a super may revert it to US English. So there is no penalty for this.
Now, if a super is deleting answers they don't like which don't break the rules, a Community Assistant may deal with them. They might be suspended or lose their powers a few days, or if this is ongoing, they may remain stripped of their powers.
The spelling for supervisor is supervisor; you had it spelled correctly in the question.
That is the correct spelling of "supervisor" (manager, overseer).
I don’t know
That is the correct spelling of the informal adjective "legit" meaning "legitimate."
No. The only proper spelling is "dictionary" (Latin for "pertaining to speech")
Spelling & Grammar
Poorly written means that the text is written bad, like with spelling or grammatical mistakes.
approximate illegitimate inanimate legitimate
Most likely is a grammatical error. The correct spelling does not contain the letter k at the end. The dictionary shows the correct spelling as picnic.
If it is a spelling error, it will underline the word in red. If it is a grammatical error, then the word will be underlined in green.
If you are sending an e-mail to a friend or close family member, (informal) grammatical correctness is not necessary, but if you are sending a more formal e-mail, then spelling and grammar count more. Grammar and spelling are especially important when sending an important business e-mail.
By fixing grammatical or spelling mistakes and clarifying the meaning without changing it.