In Canada all obituaries are considered owned by whoever their creator is. So if you are looking at Canadian obituaries- you may want to think twice about reposting them publicly. I know in 2019, a company was successfully sued for reposting obituaries online, because they broke copyright. I’m fairly certain that obits are considered under copyright until 70 years after the death of its author. So unless you know who actually wrote the obit, you’d have to wait a fairly long time to legally post it. I would definitely do your research on copyright before mass posting them, that’s for sure.
I know I personally manage thousands of Find a Grave memorials and when people upload an obit to any of them, I have Find a Grave remove them due to copyright, and they agree with me every time.