Being a very well known news site and having a paywall is one thing (although given The Guardian's financial struggles, and how many times they've had to rebrand themselves to stay in business, I'm not sure they're the best case to cite!), but being a site dedicated to what is a niche interest - when there's countless rival sites catering for the exact same thing - is something else.
I've made my feelings about Autosport/Motorsport's paywalls well-known already, but I think you're as likely to drive people away as you are to get them to sign up. Particularly when you consider that following motorsport/F1 is already expensive enough as it is, given the fees you have to pay for Sky/F1 TV, tickets for any races you want to attend, and so forth. Not many people have a lot of dispensable income to use on following their favourite sport.
We've talked often enough on these forums how damaging it is to any sport, and F1 particularly given its well known declining audience, to be behind a paywall. I therefore can't see any way it would benefit Autosport to be behind a paywall either.
The question though is how do you run a viable online site without a paywall?
Online advertising rates have cratered, and they were never high to begin with. Google Adsense brings in a pittance, direct adverts make a bit more, but trying to boost revenue can force users away and lead them to blocking ads and driving the revenue down even further. You could run things like sponsored content, but that’s ethically dubious to say the least. You could run a membership scheme that provides benefits apart from access to content, but you obviously need something to offer. You could similarly have a supporters scheme designed more as a donation, like the Guardian or a lot of smaller sites, but are people going to donate to keep something like Autosport going? I think you either need to be small and have an obvious selling point, or like The Graun have a hook (support news from liberal minded people against right-wing foreign domiciled billionaires) that gets people to donate. (Incidentally the guardian has been surprisingly successful and is becoming a profitable online enterprise)
Who knows what the right model for a motorsport site is. If you want a service that covers multiple series from across the world, with reporters who are actually there, together with the usual features and opinion pieces, at least some of us are going to have to pay.