An account exists on Socostars for one reason: to carry the clubs, players and competitions you follow to your other devices, and to give server-side alerts somewhere to be delivered. Nothing on this site is paywalled by it.
ALERTS_WEBHOOK is configured on the deployment.
You are not signed in on this device, so there is nothing to show here. Everything on Socostars works without an account — signing in only carries your follows across devices.
Self-service deletion is not wired up on this deployment. Ask the operator (hello@socostars.com) to remove the account and every row held for it; the watchlist is a single column on the account row, so removal is complete rather than partial.