Indeed, the main weakness is that their business model relies on a big shift to online buying, citing that secondhand cars are a "growth potential area" because of the currently low % bought online. The reason for this, is because a car is a complicated mechanical thing which can & does go wrong; and also, excepting nearly-new cars (and even then...) once a car starts getting older, they become distinct from each other so you want to inspect the one you're buying. Its not like a telly where its a boxed, new item.
To alter this needs a big shift in confidence level in dealers (they are silent on this....) and/or a seismic change in online vs offline buying (like a global pandemic which forces the government to close offline car dealers). Its impossible to split out the "Covid effect" from their growth, in fact you could say they ought to have made a killing on the market but they didn't seem to.....possibly because of out-of-their-control factors such as capacity to prep cars, logistics, availability of stock etc.
Sure, online buying will grow, sure Covid has moved us forwards quickly, but it cannot be assumed nor taken for granted. And you can't monopolise it either.