It seems to me like where a period would be too strong and I want the clause after to be considered equally at the same time or possibly as a counterbalanced thing to whatever is to the left of it
If it were to parse it purely linguistically, it seems like not quite a list of things but perhaps a relevant after thought that a comma would be too weak for and a period too strong


https://writingcommons.org/section/grammar/mechanics/punctuation/semicolons/
Explains it nicely. Linking closely related independent clauses is the most common way I use them.