Segwit is still not fully supported in the Core wallet [1] - change goes to P2PKH addresses and there's no GUI support for generating (or even sending to AFAIK) bech32 addresses.
While certain charts regulary show 10% usage [2], when analyzing UTXOs, the numbers are a miniscule 0.03% of transactions. [3]
[1] https://github.com/bitcoin/bitcoin/pull/11403
I think you only need a path to the person you want to pay, not a direct channel. eg if Alice wants to pay Bob, and they both have a channel to Greg, then Alice can send money to Bob through Greg.
> They haven't even implemented segwit yet,
The wikipedia[1] page seems to say that most miners implement segwit now.
* https://en.wikipedia.org/wiki/SegWit