To be fair, when ISN'T this the case?
Just looking back to 2015 (when the Sox signed Price):
Price, Greinke, Hewyard, Davis, Upton, Cueto and Zimmerman.
2016: Cespedes, Chapman, Fowler, Jansen, Desmond and Turner (what an abysmal FA year that was).
2017: Hosmer, Darvish, JDM, Lorenzo Cain and Arrietta (Darvish and JDM ended up good deals).
2018: Harper, Machado, Corbin, Eovaldi, Pollock, McCutcheon and Kikuchi (a pretty good class, with 3 "hits" and McCutcheon remaining useful enough if overpaid).
2019: Cole, Rendon, Strasburg, Wheeler, Donaldson, Bumgarner, Ryu (pretty decent class with 4 hits in the top 7, but also 3 crippling misses, including 2 of the top 3)
2020: Springer, Realmuto, Bauer, LeMahieu, Ozuna, Hendricks and McCann.
2021: Seager, Bryant, Semien, Freeman, Baez, Story, Scherzer, Ray, Gausman, Correa, Castellanos and Schwarber (Probably one of the best in recent memory. Seager, Semien, Freeman, Scherzer, Gausman, Castellanos and Schwarber are all deals I'd generally like at this point.)
2022: Judge, Turner, Bogaerts, Correa, deGrom, Swanson, Rodon, Nimmo, Diaz, Yoshida. (Still too early to tell).
Point being, in pretty much every year, and in ever class, you can certainly find flaws with players. Even someone as consistently studly as Freeman or Cole one could look at his age at the time of the deal and age toward the end of the contract as a "flaw." Harper is probably the only one on there where you really couldn't find a flaw with the player at the time of the deal.
Heck, Manny might be the single best big money FA signing I can think of (there are probably others, but he comes to mind) and even he was certainly a "flawed" player.
If you look for a "flawless" player in free agency, you're basically never going to sign anyone to a big contract.