Should I still use the MetaMask Connect EVM SDK if my users have the MetaMask extension installed?

Yes. The SDK is the recommended integration path regardless of whether the

extension is installed. When the extension is detected, the SDK delegates

directly to the injected EIP-1193 provider — it does not initialize MetaMask

Wallet Protocol (MWP), QR rendering, or mobile transports. The runtime cost on

the extension path is minimal, and you keep a single, consistent connection

surface across all environments (extension, mobile deeplink, and QR/MWP).