It's a shame that they can't transition it to a read-only archive type site, where everything is still accessible and playable- jut no new updates or content.
Edit: most users won't have the Ruffle extension, so the one great thing they could do is add it to the site with a single <script> tag :)
If you'd like to experience the games that were available on Miniclip back in the day, your best bet is FlashPoint, a big offline archive of Flash games (ships with integrated FlashPlayer and a nice UI to search for games).