Leaving aside any tit for tat arguments on funding, the sole issue of population is massive problem for likes of Roscommon. They simply don’t have the size of population to regularly produce the unique players required on regular basis. (They have 64,000 - half are women, huge number of rest are outside 18-26 age bracket. Even if their top 40 became full time athletes, they wouldn’t beat Dublin.)
Dublin always had the raw factors to dominate but back in 80/90’s they were a Mercedes being driven like a fiesta racing against alot of counties who are only fiestas. Sometimes they won, often they didn’t. Back in 90’s, they picked a panel of 25-30 and that was it. Now every grade across the huge and increasing playing pool is forensically assessed for potential… and developed and nurtured …and that dedication maintained. This is due to the brilliance of Jim Gavin and the dedication/focus of the players who make it or strive to. The problem now though is the advance of this approach maximises the advantage of having access to much bigger player pool. Hence you see the 5 in a row not being a central core of players but continuous addition of equally 2-3 players each year with the skill, dedication and mindset.