Sure he got a few scalps like Manafort, Papadopoulous, Stone, that Dutch lawyer and indicted a few Russians too.
All small fry trying to give the appearance that something was happening.
No one was indicted let alone convicted for treason or conspiracy. Short of proving that, yes Mueller is a complete dud. And Trump's still in office (getting DJT out of office was always the aim).
The Adamov Schiffonovitch show we're being treated to right now it just a cheap reboot. A bit like Highlander 2 was to Highlander. Less means, less production, less well staged, more rushed, etc. It's going nowhere. Sure they might vote for something in the house and the Senate will kill it in two seconds flat. Then what? DJT's still president.
I note that General Flynn, one of Mueller's prize trophies has still not been sentenced - are you certain that's going to happen?