it's the least cost version of all the brexit versions.
Reversing brexit: the conservatives cannot do that, they would split if they try.
JC cannot do that, Labour will lose a lot of seats, even in London.
Only a coalition government can do that, by blaming the other partner or partners forcing them to do that. The probability of LibDems winning more than a couple of seats at the next GE is very small, so such a coalition is very unlikely.
Would a soft brexit work for a generation or more?
Quite possibly. If the EU somehow manages to reform FOM and prosper (ie bringing the income level of all the new members to EU average of around 1,200 Euros a month take home pay per person), then it's easy to rejoin the EU from a soft brexit. If not, then soft brexit is still the best solution.