Verisign's SLL authentication business was spun off and sold to Symantec a while ago, but Verisign continues to operate the .com registry as a separate company.
Operating a domain registry and issuing EV certificates require different levels of trust.
Don't read too much into Alphabet/Google using other gTLDs instead of .com, like https://abc.xyz or https://blog.google -- that's separate work done by separate people on a separate team.