You don't need to keep an entire site updated just for that. Just save your work in more places than JUST artstation (locally, with backups eg), which you should be doing anyway, and you would always be able to just upload it somewhere else, should Artstation suddenly die.
I just wrote a 3k word article on this, i will post up soon, but basically, use artstation. Its where the most relevant attention is. when you update a personal website or blog noone is notified and its just like a fart in the wind. when you focus on building an artstation following, every one of your followers gets a…