in competitions sometimes clubs that are considered underdogs can actually advance far and beat big clubs. Like last season in the UEFA Europa League that never expected Atlanta to advance far to win the title which was previously an underdog club. So can happen in the Champions League this season, especially since the Champions League has only played its second match and the journey is still long and all possibilities can still happen.
Newcomer clubs cannot be underestimated, that's true but most of them are no more than memecoins that just follow the hype. I don't believe in them as underdog teams because every season there will be one of the many clubs competing. If Atalanta is used as an example, maybe this season there will be a team name that will be an underdog like Brest. This club from France got a total of 6 points because they were able to win against two teams by scoring 6 goals.
Apart from Brest, there are still other teams that are not considered that might be able to follow the teams that were once underdogs in the following seasons. Rather than guessing, it's better to just follow who they are with the new format.