It doesn't stop the top clubs breaking away, but it does make it less likely.
The top clubs would have hoped that the EU would have found in their favour, ultimately that UEFA should not be able to ban clubs from domestic leagues if they join an independent competition. Had they done so, the big 6/7 in the Prem, plus PSG and Bayern would have known they could still have had the best of both worlds and might have been more inclined to go along if enough other sides did.
Now, those clubs will be less likely to take the gamble, leaving Barca, Real et al to need to convince the likes of Napoli, Inter, Bilbao etc to join them in a break away that would not include the big English, German and probably French sides and which would lead to expulsion from UEFA. It also makes it difficult for their argument that the league would not be a closed shop, as which clubs would want to be promoted in for a season knowing it would see them kicked out of domestic competition?
The threat hasn't gone, but it should force the rogue 3 to come back to the negotiating table as such.
As for caring about UEFA's financial health, I don't think that's really what we're discussing is it? What we're talking about is the right for UEFA to help protect the domestic leagues from these greedy break away clubs looking to take even more money from the poorer sides and strange 150 years of European club football.
