The one-sided 2019 world championship is affecting television viewing figures.

RTL, the German free to air broadcaster, reports that one million fewer people sat down to watch the Barcelona race compared to the 2018 Spanish grand prix.

"As much as you have to pay tribute to Mercedes, they suffer as much as so many motor sport fans worldwide due to the current lack of excitement," RTL spokesman Matthias Bolhofer told Bild newspaper.

"The fact that this affects the viewers' interest is the logical consequence."

And Lewis Hamilton, the new championship leader following five consecutive 1-2s for Mercedes, says it is even more complex than that.

"Honestly, the cars are not hard enough to drive," he said. "Now you see 18 year olds come in and have no problems. That has to be looked at for 2021."

Hamilton also admitted the lack of competition is "not as much fun" from a personal perspective as when rival teams like Ferrari and Red Bull are fully competitive.

"When you don't have that, it's definitely a lot less exciting and not how F1 should be," he said.

"But it's not our fault that our guys are good at their jobs.

"Red Bull has improved their engine but it seems like their car is not as good as it usually is. And Ferrari has a lot of power but problems in other areas," Hamilton added.

Red Bull team boss Christian Horner doesn't deny that Mercedes appears to be cruising to an easy 2019 title.

"It looks like it's going to be a Mercedes championship, yes," he said.

"But everything changes. The year is still long."