You have to look at percentages, too. Yes, I can give you comparable drop offs, per capita, easily. Remember that F1 peaked at about 1 billion viewers. Losing 200 million over a decade is 20% over a decade. The total number is alarming, but the percentage drop is matched, and exceeded even, in other sports, genres, and TV in general. Note that TV lost 8% from year to year. What did that work out to over a decade? Hockey viewership went down by by a much greater percentage over a similar period. The NFL has fared worse, by percentage, Super Bowl excepted, of course.
Note that F1 is also a special case. Bernie, love him or hate him, had impeccable timing with TV. He sold TV deals all over the world, where they didn't exist before. He was exceedingly protective over TV rights, and sold everywhere and for very large dollars. And, when TV began its decline, he didn't stop. TV executives that had their heads buried in the sand about shrinking TV audiences, Bernie took them out back with a set of shears and fleeced them. TV executives that tried to sell him a bill of goods about TV being so strong, he called them on that, took them out back and sheared them, too. There are few things out there, bar perhaps World Cup, Wimbledon, and the Olympics, that have better global coverage than F1, and those three are events, rather than an ongoing season.
Bernie grew the heck out of F1 TV coverage, and it has nowhere to go but down in viewership when measured by TV ratings. TV deals will be expiring on an ongoing basis, and some simply will not be renewed. Some will be for less money. Liberty may find some that will pay more. In this day and age, though, increasing TV viewership from the peak that Bernie provided, mostly by pure salesmanship, will not be happening. F1's own streaming service will displace the loss of some TV deals, and will devalue others. Times are changing. Bernie jumped in at the right time and was pushed out at the right time.