Safe Wallets?

I recently opened my METAMASK,TRUST, &YOROI WALLETS after a two year hiatus from crypto. Everything was as it should be in YOROI & TRUST. All my crypto was present and accounted for. However my METAMASK wallet was empty except for .07 cents worth of Ethereum. I should have a billion Shibx that was staked on shibaswap. I logged out of all wallets and deleted the apps. Turned of my phone and left it all alone for two years. My SRPs were never shared online or with anyone’s else. If it was a keystroke hack they would have gotten all my SRPs I wonder 1)is METAMASK the weak link out of the bunch. 2)Was it an inside job? 3)Why would the hacker steal my smallest wallet? I’m just trying to figure this out and help others along the way Thanks