It is perfectly fine to review a specification, understand the intent of
the original designer, and suggest ways to better achieve the same
result. That is exactly what working groups are supposed to do. It is
also perfectly fine, if the original designer won't change their design,
to publish an alternative design that hopefully works better, and then
rely on market forces to sort it out. But it is not fine to try to
prevent the original designer from actually shipping products, either by
preventing publication of the specification or by trying to prevent
deployment.
On the contrary, it is our duty to do all of these things.
What is not fine is for participants to expect IETF to lend its support to bad
designs.