I almost agree with what you say. You're correct in your first paragraph. Most people here are basing their reasons for the sale on their political leanings and not the facts. All media are dying and it's been this way for at least 20 years. Younger people are just not buying newspapers (or watching cable news) anymore. I have always had a Star subscription but I never read it. I have it because my wife still enjoys reading it over breakfast. I prefer to go to online websites to get all viewpoints, right and left. My children read newspapers if there's nothing else in the dentist or doctor's waiting room.
I have a problem with what you say about it becoming a leftist rag. The other three Toronto papers are right wing mouthpieces, the Globe a bit less than the other two. I recall a time when all four Toronto papers had a fetish for accuracy and balanced reporting but that's not the case now. People read papers and/or watch cable news based on their beliefs, not the accuracy of the outlet.
The Star has always been centre-left (not a leftist rag) and has billed itself at "the people's paper," but it's sale has nothing to do with that. Whether or not it changes its viewpoint remains to be seen.
https://www.canadalandshow.com/political-donations-made-by-new-torstar-owners/
My thinking is that the new owners will continue with the Star's outlook on the world. Why compete with the Sun, Post and Globe who are all barely hanging on?
And, by the way, debating the editorial outlook of newspapers is a moot point because no one votes based on a media outlet's editorials. At best, they reinforce a person's beliefs.