I would recommend Greg Maxwell and AJ Towns latest replies on the mailinglist. It's harmful if people use different settings, whether that's by configuration option (-datacarriersize) or by code forks (Knots). The chaos of a "free market" for settings is disruptive for the network, which only helps its real adversary: governments. The custom Knots default of 42 bytes caused problems in the past for Samurai wallet (which they in turn used for their drama marketing). In theory it should also interfere with compact block relay (I haven't seen measurements though). https://gnusha.org/pi/bitcoindev/aBSVn7nJnrheLy5Z@erisian.com.au/