I have a webpage that implements a set of tabs each showing different content. The tab clicks do not refresh the page but hide/unhide contents at the client side.
No
I can't see how changing the page title via Javascript will help SEO. Most (or all) search bots do not run Javascript and will only read the initially loaded title that is the mark-up.
If you want to help SEO, then you will need to change the page title in the back-end and serve different versions of the page.