If you can get a friend to switch to Edge via a referral link, you'll receive 500 Microsoft Rewards points (with the ability to accumulate up to 7,500 points per month if you're feeling ambitious).

A $1.25 Microsoft gift card is 1,625 points.

So you have to refer four friends to get $1.25 off your next Microsoft purchase.

what in the fuck is a microsoft point and how do I ensure that I never hear or see that stupid term again

A Microsoft Point is roughly equivalent to one Schrute Buck.

Or approximately 0.0769 U.S. cents, non-transferable.

Recent email: "get a 4k € reward"; reading beyond the teaser/bait, it's a raffle you buy into with points, which I interpreted as you won't win anyway, so it's just throwing the points away.