I also think Gallagher will give the team a boost. But what's the point of trashing Murstein on his way out of the team? Murstein lasted longer than a lot of owners of third-rate mediocre teams. Murstein provided crucial support that kept the team going, and without that, Maury Gallagher would not be buying this particular team because it would no longer exist... the Petty name would no longer be in Nascar.
Murstein and Petty joined forces to keep the Petty team going after the Gillette-Evernham collapse. Both had skin in the game. Murstein had equity capital, Petty provided debt financing. Murstein had the controlling interest, but Petty also had significant involvement... if you believe the descriptions shared by Bubba Wallace.
Both parties were crucial to the team surviving; both could have done a better job, could have won races and championships, could have sold millions in sponsorships, but they didn't. The obstacles would have been smaller if Petty alone had not run the team into the ground before he sold off the carcass. So, I just don't see the point of trashing Murstein as he heads for the exit ramp.
[P.S. --
@AuzGrams, Murstein does not owe any money to Petty. The race team owes ~$8 million to Petty but the guarantor on that is now Gallagher, not Murstein. And did you also like it when Petty trashed Smithfield when they moved their support to SHR a few years ago?]