As an Aussie who is a big fan of Piastri and Doohan, and I have been following Lawson for 5 years, I have therefore been exposed to Sargent quite a bit, and I have to say I rate him very highly.
Lawson has been team mates to, and faster than, Vershoor, Tsunoda, Hauger, and Vips in different categories of F3 and F2 and yet Sargent has had his measure in qualifying and frankly tyre wear mostly this year. Both have been unlucky, in fact this year both Lawson and Doohan have had awful luck, but I'm sure every driver has except maybe Drugovich who had a pretty clean run.
Sargent was pretty unlucky to lose to Piastri in F3 although he had a year's more experience, and whilst his year 1 in F3 wasn't great, year two and most of this year he's been fast.
He fell away horrendously though the last part of this year, but not all down to him.
To me though, Doohan was the standout this year, so fast, mastered tyre wear, good in wheel to wheel, but the last three straight feature races he has been taken out of whilst looking pretty good (rammed under safety car in I think it was Hungary?, bad clutch then punted in Monza, then the wheel issue yesterday) I think given how much Iwasa fell away in pace yesterday, the win was there for the taking for Doohan.
Anyway, ifs and buts and coconuts...... but I see Doohan as favourite next year.....