FUD is the only reason no major service (and almost no minor services) will recognize something that would get them more customers and business?
Either FUD or maxi politics. Eg. Bitrefill and BTCPayServer refuse to list BCH (and BSV) because of politics. For Bitrefill it is esspecially stupid since they lose out on business.
There is also fear. They fear the backlash from Maxi's on social media, they fear blockstreams puppets attacking them so they suck blockstream dick rather then do the right thing.