Even the US. dollar is inflationary and lost its purchasing power over time, it's terrible idea to back the US. dollar by Bitcoin. You can connect this idea with the Terra Foundation Guard which uses some cryptocurrencies including Bitcoin and how it failed to protect Terra LUNA token and its algorithmic stable coin UST.
Luna Foundation Guard Adds to Terra Reserves With $880M LUNA 'Gift'. 1 month after that, the Terra death spiral happened.
Lastly, don't believe in politicians as Robert F. Kennedy is only trying to make noise, get votes for him. Politicians usually don't keep their promises.
It's nothing like Terra/Luna at all. If it actually goes through, the only allocation to bitcoin would be sub 1% of t-bills because there will also be allocations to gold and silver platinum. Read the article.