rise records actually has a pretty diverse lineup of artists now. and the same you said about metalcore can be said of any genre. for example pop punk would be intro riff + verse + bridge + catchy chorus + verse + bridge with minor change + chorus + ending bridge + chorus, song finished. current rap would be: instrumental or acapella intro + verse + chorus feat. someone + verse of someone else + chorus feat someone + verse combination of 1-2 people + chorus , song finished. bro-dubstep would be: female singer intro + brief calm + bass drop wubs + insert female singer again + mixture of calm and wubs + calm female singer outro.
everyone holds on to certain music types and sees other genres as "all sounding the same", its just a matter of perspective.
You are very correct in that there is a certain general musical structure in different genres. You pretty much undermine your argument because the reason we all love the earlier MMF is because they did NOT adhere to this strict structure. Some songs on Sleepwalking had no chorus's and only one or two recurring riffs.
You are also correct in that in the end this comes down to taste, but you cannot deny that the breakdowns in the past two albums(chiefly Challenger) are very similar. To me it seems like pure lazyness, like they didnt know what to put in between sick guitar riff and catchy chorus, so its just "HEY LETS PUT IN GENERIC ONE NOTE BREAKDOWN , and try to make it sound a little different than all the rest of these parts on the album." These last two albums lack the diversity and flair of their older material. Alas again I say: it all comes down to taste.