It is already widely known that Renault would have left F1 if the V8 engines had stayed, while Honda would not be coming back in 2015 if the regulations had not changed either.
But now Thomas Weber, the Daimler board of management member who is head of R&D, has made it clear that the German car manufacturer's commitment to F1 would also have been in doubt if things had not changed.
When asked if there was a question mark over Mercedes' future in F1 if the sport had kept the old engines, Weber told AUTOSPORT: "Yes."
Although a departure may not have been immediate if Mercedes was winning, he reckoned that as soon as the success stopped then there would have been no reason to stay.
"It would have been better [if Mercedes was winning], but we as the board, we are independent," he said.
"We are responsible for what we are doing, and it's not a good argument to stay only because we are winning races.
"The only argument could then be marketing. But to do motorsport only because it is marketing, for me the discussion is too short."
Rosberg leads Bahrain testing
Weber, who attended last weekend's Bahrain Grand Prix to see Mercedes take its second consecutive one-two finish, said that the German car manufacturer had never felt F1 technology was more relevant than now.
"In former times, it was important for me to go to a Formula 1 race just for fun," he said. "Now it's part of my business.
"Never before were we so close technology-wise to the technology we need in road cars today. The engine downsizing, turbochargers and hybrid technology. That's the name of the game now in F1."
He has called on the sport to do more to educate fans about why the new fuel efficient rules are better.
"We have to explain why this is the right direction and there is, for me, no alternative," he said. "
"These guys [the critics], they believe they can continue everything forever. They don't really know how complex and how dangerous a discussion about F1 was in the public - even in some supervisory boards.
"For me, if we wanted to protect our business for the future, then we had to change our business system."
LAUDA: F1 DEAD WITH NO NEW ENGINES
Although there have been complaints that the new engines are not as exciting as the old V8s, Mercedes non-executive chairman Niki Lauda is adamant that that the sport would have been on its knees if change had not happened.
With Mercedes joining Renault in potentially quitting the sport without the attraction of new hybrid technology, Lauda thinks F1's future itself would have been in peril.
Speaking to AUTOSPORT, Lauda said: "If people don't want these [turbo] engines to come in, then stick to the old engines and make a garage type of racing.
"Then there will be no more big manufacturers coming in, and then you will see where the fans are - because they will be no more fans.
"It is the right thing to do to have a modern, future-orientated F1."
- Sports & Recreation