Emily, that funding for VTR has been cancelled is tragic, but I can hardly say unexpected. Some historical perspective -

Since the 1960s the Rockefeller Foundation, the MacArthur Foundation, the American Petroleum Institute, and an unending list of proxy organizations have been enlisted to further the business interests of the world's most lucrative product: oil. Early on, nuclear energy was recognized as a threat to those interests. It had nothing to do with carbon emissions, the significance of which was barely understood at the time, but that a nearly-unlimited supply of energy had become available from uranium, a nearly-ubiquitous resource. That electricity could be "too cheap to meter" was not an overstatement - it had the potential to render oil (and natural gas, and coal) obsolete.

One of the most successful marketing strategies adopted to counter the threat was mongering fear. With the 1962 Cuban Missile Crisis fresh in mind, associating nuclear weapons with nuclear energy had already shown promise for slowing public acceptance. So funds were allocated for what would be, after oil, the industry's second-most lucrative investment: anti-nuclear activism:

"Friends of the Earth was founded in 1969 in San Francisco by David Brower, Donald Aitken and Gary Soucie after Brower's split with the Sierra Club because of the latter's positive approach [support] to nuclear energy. The founding donation of $500,000 (in 2019 USD) was provided by Robert Orville Anderson, the owner of Atlantic Richfield Oil Company."

As nuclear energy marshalled on into the 1970s, however, it seemed to be less dangerous than Friends of the Earth portrayed it to be. A secondary strategy (nicknamed "Just Around the Corner-ism") suggested harvesting energy from the atom, though currently "unsafe", might one day prove useful if the kinks could be worked out. It just needed time, they claimed, knowing time could be stretched indefinitely. Nuclear energy was re-christened "advanced nuclear" - a technology that was just around the corner, they said. 

Fast forward to 2021, and the VTR will finally put advanced nuclear within reach. Left with no other options funding is cancelled - and that the world's most lucrative industry played a central role is indeniable.

What are the "legislative opportunities to rectify this error" to which you refer?

The VTR only function is to develop fast reactors. Such machines have a dismal track record in terms of technical, operational, safety and economic competitiveness. Further, the machines require reprocessing of spent fuel and that is a huge can of worms in and of itself.

Taxpayer support for nuclear development is better spent on other reactor types that have a much better shot at being competitive.

Sodium cooled reactors have been multi-billion dollar failures in France, Japan and other countries. Too hard to operate owing to the fact sodium catches fire in air and reacts violently with water. Then there is the problem of sodium voids in the core (e.g. caused by boiling if sodium gets too hot from flow blockages) causing the the reactor to become highly unstable. 

Sodium reactors are more trouble than they are worth. Pragmatic engineering conclusion.