Companies that do not respect RFC email addresses are simply breaking the internet. Email addresses are not unilaterally specified by your marketing department, they are at this point, internet infrastructure.
Agreed but I don't think they care about RFC's. Rather they want to be able to track people and be able to sell or leak, but really sell your email address and email canaries put a stop to that behavior and they don't like it.
https://datatracker.ietf.org/doc/html/rfc5322