If you define any and all customer engagement as "marketing," then yes, but not all marketing is objectionable. This is the kind that most of us welcome because it materially improves our experience as customers, both individually and in the aggregate.

I will add that in addition to the personal email from the GM at PH Zurich, which references an issue I had with the bathroom stopper being inoperative, I received a subsequent follow-up email from the FDM promising to upgrade me to Corner Suite on my next stay. Which they faithfully did, all the way from a View King, about a year later. That's the kind of customer engagement you're missing out on based on an utterly irrational objection to "marketing" emails.