List of major Open Problems in Computational Complexity and their Likelihood?
What you are searching for could be Some Estimated Likelihoods
For Computational Complexity by R. Ryan Williams, 2018.

Here are "Some Estimated Likelihoods for Some Major Open Problems" in that paper. Note that "The numerical values of my 'estimated likelihoods' are (obviously) nothing
too rigorous. What is more important is the relative measure between problems."