I don't think anyone would complain if they changed track limits to white lines.
I would. What's the point of having kerbs if you're not allowed to ride them?!
I started doing motorsport photography back in 2004 and the generally accepted rule, at least in the UK, was that you were on track if you had at least a pair of tyres inside the white lines. Obviously, some cars could push this more than others, but generally people would have the space to try harder, go faster, and not be In danger of being penalised for driving like this...
In recent years though, UK circuit owners started getting all pissy about cars making a mess of their grass and in 2014 the MSA issued new directives clarifying track limits and calling for stricter penalties those exceeding them. The guidance was based on where the outer wheels reached, rather than what was left on track. You can read the MSA notes
here.
In short, what they say is that where there is a kerb, that is an extension of the track and may be used as such, so the driving on most of the video is completely legal.
The unfortunate result of this, in an age of crap economies where motorsport is already dying on its arse in many series, is that motorsport is now a much less enticing and exciting for the spectator. All of the flamboyance is gone because drivers won't push overtaking opportunities which risk them running a bit too wide and being penalised for not respecting track limits.
I remember when it first came into force, drivers in one of the series I cover were getting penalties and having quali laps not counted, and having to view videos with the CoC to work out where they had run too wide because they were driving as they always had on the same circuit.
Silverstone and Donington have both praised the changes as they have seen lower operating costs from not having to repair the grass as much, but a few years ago, I'd cover dozens of race weekends each year, including single seater and GT cars from club to FIA level; last year I did two.
My take on the video is that, with the exception of a bit of grass at T1 and the crazy line at T4, which was way more than I thought you could get away with, and maybe the first of the s-bends, it was an excellent lap. Certainly in line with what I'd aim for.
If you're not trying different lines and seeing how much track you're allowed to take, you probably aren't practicing enough to ever get near the Top 10 times. These guys don't just rock up a couple of hours a week and blitz it, they take time and put in the hours to learn the nuances of every track. If you don't have the time to do that, that's fine and you'll be matched with people at your level, but don't complain that people are faster than you by driving within the same set of rules as you.