Which 49ers Player is the Likeliest to Step up in 2025?

2025 will be the season of opportunity for the 49ers.
With so many players departed in free agency, there are a handful of candidates on the 49ers who will need to step up. They need to make up for their losses.
The 49ers are banking on these players along with the rookies they will draft in a little over a month from now. Pro Football Network believes it will be Malik Mustapha.
Here is their explanation for choosing him.
"Safety Malik Mustapha showed that he has star potential during his rookie season. Mustapha, a fourth-round selection in last year’s draft, far exceeded expectations in Year 1. He started 12 games and registered 71 tackles, two tackles for loss, one interception, and five pass breakups. He played 728 snaps in 2024, but he stands to have even more opportunities next season."
It's difficult to argue against picking Mustapha. I fully expect him to be a solid player next season and build upon his promising rookie campaign.
However, I'm going in another direction. I don't have Mustapha as the likeliest 49ers player to step up because he already did that in 2024.
He is expected to be that cornerstone player now, so it's not surprising to see him take a leap. It's execpted at this point because he stepped up his rookie year when no one saw it coming.
The player I think that will step up is linebacker Dee Winters. He stands to gain the most out of all players who need to fill in for the departed free agents.
The 49ers need a new partner in crime with Fred Warner now that Dre Greenlaw is with the Broncos. Winters has to be that guy to do it.
It's unlikely going to be any rookie they draft in a month from now. It has to be Winters who can thrive under defensive coordinator Robert Saleh.
He showed a lot of promise and some improvement last season. If it wasn't for the force feeding of De'Vondre Campbell, Winters would have gotten adequate experience.
Also, remember that Warner was high on Winters after OTAs last year. He likes what he sees out of Winters and isn't one to bestow empty praise.
Winters has the primetime opportunity to step up. It'll be nearly impossible to replace the emotions that Greenlaw had, but he can get fairly close to the production.