Are we really using website design choices as a valid target to discredit someone's opinion on the technical merit of an init system?

Can I use Lennart's inability to buy a properly sized polo as a reason why systemd is bad?

Yeah. The guy has an ugly website. But he has specific points about mistakes that systemd didn't learn from and is repeating. Did he list 'it's too user friendly' as one of those mistakes? In fact, one of his core arguments is that there will actually be an increase in complexity and reduction in user friendliness due to design choices that have been made.