I mean it'd suck if the website went down for good as some legitimately good (I know good is extremely subjective here) artists are exclusively (IE commission openings ONLY happen through FA) on there, but at the same time; At what point are you just considered completely ignorant/arrogant of the going-on's of the website you host your business on primarily and never considered branching out at all? Is the only reason you haven't jumped ship yet is because others who view your work just refuse to leave FA as well?
That's pretty much the case for most people who build up a business via a specific website. Both brand loyalty, and community bases. There are artists on twitter, who only communicate through that.
Although, artists may be inclined to move to another site, like moving from Fiverr to Ko-Fi, as Fiverr takes a 20% cut of orders, vs Ko-Fi's 5% on commissions (or none if paying for pro features. That exclude's Paypal or Stripe's cut of course.
The only time you see them branch out is if they either have the time, the tools to make post syndication possible (like PostyBirb) or are at risk of being kicked off a specific site.
A bit off topic, but an example of that latter process: Reagan Lodge (SulaCoyote) for example got temp banned on FA during the stormfront leaks occured, and His identity was connected to the site.
I believe that only got removed after some apology tour, and probably backroom talks with Neer & Co.
After that incident, Sula already had his own site for his project and livestreams on Twitch, but eventually expanded out to Telegram and Parler (before site archival and cancellation)