>>48406401Lopunny is not "underrated". When it comes to public perception Lopunny is #2 when it comes to that "side" of Pokemon. I've seen videos on YouTube with over a million views with it on the cover when dealing with that type of subject.
In terms of popularity it's also very popular and doesn't lag very far from the piece of cloth you mentioned. At least as far as image archives with voting system would allow us to gauge.
>>48403491Lopunny shows up quiet a bit in the most upvoted pictures for the Pokemon. Even if we don't have a super comprehensive poll we still get avarages like this or the contest held here in /vp/ which Lopunny came only 3 votes away from breaking even with Gardevoir. Not to mention the shotout it got in the anime as a "you just know" moment or being part of team charm in PMD.
If you mean raw numbers well that has more to do with the fact that Gardevoir came first, it's also a fan favorite, just like Lucario who also has a shit load of porn, and is in a semi-shill status. But still just because some Pokemon have a greater amount of porn doesn't negate Lopunny's popularity, it just doesn't get as much porn.
But the premise is wrong because you make it sound like Gardevoir dominates the pokeporn meta and, well, it really doesn't. If those score numbers from paheal and xxx are any indication it's strong and popular but nowhere as overwhelmingly so as you make it sound. Both are probably not very far in terms of popularity and no Pokemon truly dominates the r34 sphere.