Can't we setup dns adresses in dhcpd? Yes we can! https://manpages.org/dhcpd/8 (After BOOTP support)

In 2005, I installed a stage 3 gentoo on a pentium MMX 233Mhz with 32 or 64Mb of RAM. As I was sleeping at night and at uni during the day, it took me 3 days to install the base system. No GUI.

If you read the link, you will understand that you can decide for every network interface a personnalize DNS. Not simply a DNS to the whole network, or by machine. Also, 99.99% sure that any modem router box combo can disable the DHCP and act as a bridge.

Note: the question I wrote was a guenuine one, and not sarcasm.