> I believe that a good reason not to wish your node to be segwit
compliant is to avoid having to deal with the extra bandwidth that
segwit could require. Running a 0.14.2 node means being ok with
>1MB blocks, in case segwit is activated and widely used. Users not
interested in segwit transactions may prefer to keep the cost of their
node lower.
If the majority of the network decides to deploy SegWit, it would be in your best interest to validate the SegWit transactions, because you might will be downgraded to near-SPV node validation.
It would be okay to still run a "non-SegWit" node if there's no SegWit transactions in the chain of transactions for your bitcoins, otherwise you cannot fully verify the the ownership of your bitcoins.
I'm not sure the practicality of this in the long run, but it makes a case for having an up-to-date non-SegWit node, although I think it's a bit of a stretch.