Very honestly, anytime I see someone do a "x goals in x appearances" I immediately think they must be purposely trying to hide something. Acting as if a 2 minute sub appearance is somehow the same as a 90 minute start is insane. It is SO easy these days to pull up the exact number of minutes played, that the only genuine reason I can think for this misleading(the kind word) stat pulls is manipulation of the data because otherwise it doesnt support their argument. If either Chermiti or Broja score 1(seeing neither has had more than 150 minutes on the pitch) they instantly become more prolific than DCL.
If you want to have a real discussion on it, use the real stats.
Beto in the PL the past 2 years: Goal every 384 minutes
DCL in the PL the past 2 years: Goal every 390 minutes
Cenk Tosun: Goal every 264 minutes
Theo Walcott: Goal every 450 minutes
Richarlison: Goal every 259 minutes
If you want to take a list of terrible players and say "look, hes better than some of those" I guess you can, but wont do you any favors. Being worse than Beto and Tosun is a hard argue. You are correct in that DCL is indeed better than Rondon and Sandro, so thats a plus.