Only as long as Matt deigns to allow your server to access his servers and deigns to allow the plugin authors who you depend on to log in to his servers.
WordPress has no governance, it just has Matt, and wo betide anyone who ticks him off (or who relies on any developers who tick him off).
WordPress.com doesn't support many of the plugins out there (or at least not on the price tiers I can see) -- but I happily used it for https://librefm.wordpress.com for a number of years.
Of course, WordPress.com is updated differently to a blog running the wordpress.org code.
WordPress has no governance, it just has Matt, and wo betide anyone who ticks him off (or who relies on any developers who tick him off).