As per transfermarkt :
Asensio Market value : 75 million euros.
Ousmane dembele Market value : 80 million euros.
Now, Let's look at their stats this season, (In La liga, CDR & CL)
Ousmane dembele : P:24 G:2 A:7 (Contributed to 9 goals in 24 matches)
Marco Asensio : P:45 G:9 A:5 (Contributed to 14 goals in 45 matches)
The current market value of both players is nearly the same, but we can see from the stats, that the stats of Ousmane Dembele are superior despite being his debut season in new city, new system, new language, new coach & new league. While, Asensio is playing his second season, in the same city, under the same system, same language & the same coach & same league.
Still, RM fans rave about Asensio, saying how great he has been, the best youngster in world, next raul, blah blah. And, we just keep criticize dembele about his lack of defending, not that sound with tactics, dumb, lazy and all that. Despite, the stats show a different story. So, be a better human being and try to encourage our youngsters. If you want to criticize, atleast give him some time.
(Many people will argue that Dembele was bought for 110M + bonus, while Asensio was bought for 3.5M. But, they fail to realize that its not the player's fault, it was because of poor negotiation from our board, in fact the player went on a strike to move to us, he did his best. That's why, I have compared both the players with their current market value, because that's their actual worth.)