This is standard verbiage.
They also are offering 100% refund. What's the problem?
Assuming you can get a guaranteed refund, no questions asked, no quibble, no hassle etc, then it's not a massive problem. I still don't think any retailer should be selling goods they know are broken: You are setting your customer up for an incredibly disappointing experience and there is no guarantee they know about the refund availability.
Additionally I don't think Microsoft should be
(1) Using incredibly charitable language to describe the issues the game has
(2) Implying that the performance issues will certainly be resolved by updates
The language needs to be more visible and stronger:
"There are known significant performance issues on the Xbox One and Xbox One S versions of this game. There are also known significant bugs that affect all versions of the game. The publisher has announced patches aimed at remedying these problems during the coming year. Any purchaser of the game who wishes to have a free refund, no questions asked, can request a refund at
www.placeholder.com"