I think things will bounce back at some point. Pahokee has always been cyclical as a smaller school. Glades Central's struggles are more surprising to me.
Palm Beach County football has been an interesting animal for a long time. Recruiting has been full-bore since the 90s. Back then, we had a lot of really odd districts for purposes of high school demography. For instance, John I. Leonard got about 8 blocks of the north side of West Palm Beach, entirely surrounded by Palm Beach Lakes' district. Olympic Heights (then the West Boca district school) got a small area of inner city Delray, as did Spanish River (then the North Boca district). Those districts were borne out of desegregation compliance issues in the 80s. During my time in high school, 2001-2005, the districts became much more normalized to only the local zone. The public schools recruited. The private schools recruited. There were high profile transfers long before the FHSAA granted the green light. It was common knowledge.
These strange districts, as one might imagine, led to some highly uneven programs in 90s Palm Beach County. The head coach REALLY mattered (e.g. Daniels at Dwyer).
But the Glades programs didn't have funky districts and they always had good coaches. Post-2010, the parents are just more willing than ever to send their kids east (often Royal Palm or Palm Beach Central) just to get them into a more stable and economically advantaged environment. For people who have never been there, it is hard to explain how tough Belle Glade really is.