Well, first of all, no Power 5 schools played Jackson State this season. They only played one FBS team, ULM, and that was their only loss of the season. One five-star recruit might catch them up to ULM, a 4-8 team from a Group of 5 conference, but it hardly makes them a threat to any big boys. The last time before 2021 that they played an FBS team was Southern Mississippi, who crushed them in 2018.
And why should Power 5 conferences try a power play against FCS teams to keep them from recruiting better players? That's just stupid. Honestly, if you're a power 5 conference team and a five-star signs with Jackson State instead of a Power 5 school, that's a good thing for you--you will never play Jackson State anyway, so that player will never be a problem for you.
Top-notch recruits have signed with HBCUs before, although it was rare. Eddie Robinson and Doug Williams used to get them occasionally at Grambling. Deion pulled it off because he's Deion. If he stays at JSU, he will get one here and there. But it won't make any real difference. Most kids are going to go for the big-time if they can. This is just the football version of when Adonal Foyle spurned Coach K to play for Colgate.