When having displaced the ISP-supplied DSL/ADSL/SDSL router at a premise using DHCP OPTIONS using a FreeBSD/Linux and ISC dhclient at many locations, and that is the client-side of DHCP.
And ISP likes to have their custom routers (which is a DHCP client, BTW) respond in all sorts of funky ISP-specific DHCP key/value sets.
Right now there's no rules engine for the DHCP server to dynamically generate options. Sure, you can't embed Lua scripts in the server at this point.
But bro, this has nothing to do with the discussion here. The DHCP client works fine, has no such concerns or issues. Stop blowing smoke.