One of the big stories following the USMNT's failure to qualify for the 2018 World Cup was how CONCACAF nations have caught up to the United States. Most credit the tightening gap to MLS's induction in 1996, giving the region's smaller countries a stronger platform to develop their national team players. Jamaica's head coach said earlier this summer that "MLS has done a lot for our football back in Jamaica" after they upset Mexico in their run to the Gold Cup final.
While the idea of MLS strengthening national teams seems to line up on paper, Elo ratings don't show much of an improvement in the gap between the top to the bottom. Looking at the top twelve teams in the confederation, only a handful of teams have shown significant improvement since MLS's inception in 1996.
| nation | 2017 elo | 1996 elo | 2017 slice | 1996 slice | change | highest in MLS era | lowest in MLS era |
|---|---|---|---|---|---|---|---|
| Mexico | 1887 | 1824 | 10.1% | 10.1% | -0.01% | 1970 | 1645 |
| Costa Rica | 1763 | 1591 | 9.4% | 8.8% | 0.61% | 1848 | 1524 |
| United States | 1741 | 1652 | 9.3% | 9.1% | 0.16% | 1872 | 1629 |
| Panama | 1644 | 1273 | 8.8% | 7% | 1.74% | 1737 | 1267 |
| Honduras | 1573 | 1509 | 8.4% | 8.3% | 0.05% | 1767 | 1478 |
| Jamaica | 1509 | 1442 | 8.1% | 8% | 0.08% | 1682 | 1444 |
| Canada | 1516 | 1559 | 8.1% | 8.6% | -0.53% | 1713 | 1471 |
| Guatemala | 1495 | 1439 | 8% | 8% | 0.03% | 1621 | 1407 |
| Haiti | 1469 | 1293 | 7.8% | 7.2% | 0.7% | 1576 | 1312 |
| El Salvador | 1414 | 1482 | 7.6% | 8.2% | -0.65% | 1568 | 1314 |
| Trinidad and Tobago | 1423 | 1523 | 7.6% | 8.4% | -0.82% | 1651 | 1372 |
| Cuba | 1292 | 1494 | 6.9% | 8.3% | -1.36% | 1613 | 1292 |
The graph shows the Elo ratings for each of the twelve listed CONCACAF nations, dating back to 1980. Most of the bottom teams have continually raised their Elo rating since not only 1980, but also 1996. Unfortunately so have the top teams. While Jamaica has raised their Elo rating from 1996 by 67 points, the jump is minimized when comparing the rest of the region's improvement.
Looking at the green-ish, blue-ish table, we can see the rise in Elo ratings per nation, as well as growth compared to the region. Columns 2017 slice and 1996 slice divide each nation's Elo rating over the rest of the region. For example, Mexico's 1887 is 10.1% of the total Elo ratings of the twelve listed teams. (Both "slice" columns add up to 100%, a whole pie.) So while Jamaica increased by 67 points over the 21 years, their "slice" only increased by .08%. Jamaica, shown in the line graph, made substantial gains prior to MLS but developed at a moderate rate after 1996. They are almost exactly positioned in CONCACAF today as they were in 1996.
As for countries who have grown since 1996, Panama (+1.74%), Haiti (+0.7%), and Costa Rica (+0.61) lead the pack but it's hard to place that all on MLS. For starters, it is such a small increase, the rise in Elo ratings could easily be put on the federation's investment in their youth system. Secondly, the current average age for Panamanians in MLS is 26.4, an age farther from development and closer to the player's final product. While MLS brags about their diversity - and for good reason - the eight Panamanians and twelve Jamaicans in the late stages of their career aren't going to revolutionize their respective senior teams.
MLS has had its successes in the past, but crediting growth of national teams isn't backed by numbers, especially considering how a number of nations have dropped off since 1996. Trinidad and Tobago was 129 points behind the US in 1996, but now are a whopping 318 below the US, and that's after their upset win in qualifying. There were 24 Canadians in MLS in 2016, but their Elo rating has suffered as well, dropping 43 points.
On the other side, Mexico's Elo rating has jumped 63 points, but how many senior caps are coming for MLS players over Liga MX? Not many. A shift in 50-100 points over two decades (4-5 points a year) can't solely be credited to a new league. MLS has surely made some impact on smaller countries, but it's likely as much as the NCAA's influence on young players, or a number of other factors that play into player development.