Is this business model viable?
Did Bernie get out at the right time?
I agree with the comment that Bernie is responsible for a lot of the mess, there's been issues in F1 for a long time he hasn't addressed and also failed to move with the times.
Clearly one of the main new issues is media and distribution as the world is a very different place for watching video of any form, F1 is being largely relegated to expensive pay per view when now it's possible for people to watch videos bypassing the TV entirely. It's clearly not good for the sport when it's increasingly restricting who can view it.
The distribution of the costs amongst the teams is a big problem which Bernie is to blame for, the teams at the front get huge amounts of money (Ferrari always receive a large amount regardless of how well they do) while teams at the mid to back get very little money. In turn this means the teams at the front can stay there and the teams at the back struggle to ever progress and are often on the verge of bankruptcy. This is a problem Liberty Media are going to attempt to address in 2021 in an attempt to balance out the teams and hopefully improve the racing as particularly in the US, the fact that only a couple of teams and drivers are likely to win a race is seen as one of the main reasons F1 hasn't done as well as it should in the US which is a big market.
The rules are clearly another problem although not a new one either and will probably always be a challenge. Manufacturers complain that the current rules are very restrictive which impedes innovation and variety in the cars, in an ideal world it would have been good to see the move to hybrids being optional so that teams who could make it work could take advantage of it at the cost of reliability and complexity whereas the likes of Renault could have stayed with their simple V8 when the hybrid was problematic for them. Then again when you see the performance difference in the cars with restrictive rules it's likely the differences would be even worse.
Other series have managed with much more diverse cars but then they've always to try and balance the rules to keep the racing close which can work well at times but not at others leading to controversial wins like Ford's recent return to Le Mans.