If you run a custom kernel chances are you're not affected:
# CONFIG_MPTCP is not set
27 karma · joined October 19, 2016
# CONFIG_MPTCP is not set
Generally speaking I do not give course to such employment offers, in other the tax rate for incorporated individuals/small business is too high.
In regards to thw reasoning behind this, I believe it's mostly a question of company culture and perhaps the expenses the employer needs to pay (gov tax, etc).