Modal Windows absolutely can be shared with a link if done well. Open the modal as an overlay and set the url with javascript. Then also have a noscript tag whi

Modal Windows absolutely can be shared with a link if done well. Open the modal as an overlay and set the url with javascript. Then also have a noscript tag which contains a link to that (modal) page. On the server side you just need to make sure that you can render that page and serve it. This is pretty much how imo. modern SSR frameworks like sveltekit are intended to be used. Of course if non-js users aren't a concern, you can do this with an SPA too, the client side routing just needs to be programmed right and the server needs to serve the bundle correctly.