Everton signed Jack Grealish on loan with an option to buy. The purchase option is £50 million. I think it's a great transfer for them. Grealish hadn't been getting much playing time at Manchester City for the past two seasons. For him, moving to a team where he'll play regularly is a good move. Maybe he won't have much of a chance to win trophies, but he'll have the opportunity to play consistently and take on a leadership role in the team. He could play a role similar to his Aston Villa days.
Truly Jack Grealish was an excellent player when he was still playing with Manchester City,he has won trophies for pep Guardiola and have led his team mates in several victories. Jack Grealish was one of pep Guardiola favorite player alongside erling Haalland but looks like Grealish hasn't been having a good time when he was still a player of Manchester City due how he has been warming the bench while his teammates enjoys enough playing time. Maybe Jack Grealish relationship with pep Guardiola hasn't been that good perhaps that could be the reason why pep Guardiola decided not to be giving him adequate exposure. However I think Jack Grealish decision to leave Manchester City for everton was for the best interest of his career. Like you have said, although he wouldn't be winning trophies in Everton but at least he would be allowed to playing important matches while in Everton.