Unfortunately, there is a current MetaMask bug that redirects to the app store rather than the MetaMask app when selected. This bug almost exclusively affects wallets updated from older versions, and also occurs in other wallets (e.g., Coinbase Wallet). Our development team is trying to find a way we can circumvent this bug without requiring readers to do anything, but we’re limited in what we can do since we have limited control over issues coming from the wallet providers and/or device operating systems.
Check out “How To: Fix App Store Redirection When Connecting MetaMask via Wallet Connect on Mobile” for the solutions you can use while we try to improve the experience.