I will never understand people obsessed with denigrating the HW landscape. The last era was poor too and nobody really cares. Watch the good fights and move on.
Spence vs Brook was pretty disgusting. Thurman was the other top dog at WW and had wins over Porter and Garcia. Spence had 1 single world level win against a Kell Brook that just got his eye socket broken by Golovkin. One of these guys was instantly placed on the p4p list and the other was called a hippie.
Spences P4P ranking is very overblown, hes consensus top 5-4 for beating Mikey Garcia a LW (not even the top lw att) who jumped up 2 weight classes and looked terrible in both his WW fights and a SD over a guy who loses to the top dogs but makes the fights tough.
Jennings never beat a top 20 opponent during a weaker period than now, so hard to put him in any top 10. Except if you work for Ring Magazine and actively promote fighters on the American circuit beyond their level of achievements.