If you thought this was too good a deal to be true, I guess Microsoft agreed. A short excerpt:
"You can no longer claim a trial of Xbox Game Pass for £1/$1, just days ahead of Starfield, the year’s biggest Microsoft launch.
“The option has been removed from Microsoft’s Xbox Game Pass sign-up website (thanks, XGP). Now, you must simply pay the full amount for your first month.”
Of course, it was a bait tactic to get subscriber count up. Subscription services are cancer, they use cheap tactics to grow rapidly and then cut them off once enough people are hooked. This was an inevitability.