I'm not sure about Lampard. I think he's done OK with some favourable situations.
Chelsea had a CL winning squad at his disposal and managed a 4th place league finish, an FA Cup final defeat and a 52% win record over 80 odd games. Also got absolutely whacked in CL KO by Bayern.
At Derby he scraped into the playoffs despite having 3 of the best young players in the league at his disposal (Mount, Tomori and Wilson). Admittedly there were some decent teams, managers and players in the Championship in 2018/19 (namely Leeds, Villa, Norwich, a surging Sheff United) but his win record was again 40-50%.
At Everton he's in a situation where he hasn't got one of the best squads in the league. It's a new challenge for him. Maybe one he'll excel at. Maybe he's learnt a lot from time at Derby and Chelsea. But at the moment there's nothing in his managerial CV to suggest he's more than an average manager. Big risk (with potential big upside if he's learnt from previous job) appointing Lampard in the current situation.