Technically no — Promotions tab placement isn't a deliverability failure, it's Gmail's content categorization, and it's a very different thing from spam folder placement. That said, it does hurt open rates in practice since a lot of people rarely check that tab. It's usually driven by content signals (heavy use of promotional language, lots of images/links, marketing-style formatting) rather than domain reputation. Writing emails that read more like a personal message — plain text, minimal formatting, no big promotional banners — tends to land in Primary more often, especially for cold outreach.