So how many sporadics would be left if we run the same on 6-state TM?

Very many - I think the number is several thousand. Several sporadic 6-state machines have been solved, though, and there are currently about 2400(?) unsolved machines. Among these are several Cryptids, machines whose halting problem is known to be mathematically hard

You guys need a blog to chase these down.

If nothing else, it’ll inspire the next generation of mathematicians.