Regime Change is on my to-read list!
I am quite sympathetic to the post-liberals, but not firmly convinced they'll ultimately have all the answers.
The follow-up book, Regime Change, offers some alternatives: https://www.amazon.com/Regime-Change-Toward-Postliberal-Future/dp/0593086902
Maybe our liberal culture will accept some form of pluralism. Still, I think it will be hard for people in a liberal framework to accept less liberalism, so I don't know how realistic an alternative this is.
A post-liberal alternative is, in many ways, a pre-liberal political system dating back to ideas from Plato’s Republic. Liberals trying to equalize the few and many is, at best, a fiction and, at worst, a nefarious, systematic way for the few to exploit the many by shunning responsibility in the name of liberty. Post-liberalism tries to reassert that difference constructively: the “aristo” use their place of privilege to serve the common good for the many.
You're right. Much work must be done to make post-liberal thought practical, but I think it starts from a stronger philosophical foundation than liberalism.
Discussion
No one will have all the answers for how to live together while we're still in this world. The best we can do is understand that social hierarchies are natural and order society toward the common good.