The 24-year-old racked up 748 yards as a rookie and followed it up with 826 in 2021, while scoring five touchdowns in each season.
Lynch has been impressed by what Aiyuk has shown both on the field and in camp practice, and has backed the man from Arizona State to grow in stature in 2022.
"I don't know if anyone's worked harder this offseason," Lynch said via NBC Sports Bay Area.
"You talk about a kid who has made a giant leap and some guys you hope that this is his year.
"I know it's going to be Brandon's year because of the work he's put in and because, you know, when a guy is just doing it every day, that translates to the field, and it translates to game time."
Lynch also identified one of the key factors in Aiyuk's early success with the 49ers - his relationship with quarterback Trey Lance.
"Really excited for him," Lynch added. "And he's earned that with the way he's worked, and he's also smart. He hung out with his quarterback all offseason.
"So their chemistry is incredible right now, and it's going to be fun to watch that come into fruition as we start this season."
The 49ers will travel to Texas to take on the Texans at NRG Stadium in their final pre-season game ahead of the 2022 campaign.