I'm going by the article by Ian Boyd.
https://www.sbnation.com/college-fo...football-offenses-defenses-recruiting-players
Of course a RANGE is more appropriate in describing ideals, because no two situations are identical. If you use 9 scholarships on DE's, that's fewer scholarships you can use elsewhere. Sometimes you need to do that, if your talent is not top notch. If you have elite DE's, though, then 6 means you're three-deep in a 4-3 system. In that case, you might be better served spending the scholarships on OL or somewhere else where you aren't so deep and talented.
If you don't believe the article I linked, then what we can do is go through the top 10 teams for the past few years, and see how they allocate their scholarships. You'll notice that there is some variation, but that it falls roughly within the range given:
Offense: 41 total
Defense: 41 total
Specials: 3 total (K, P, long snapper)
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Offense....
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