I am just having this problem. Actually getting SPF, DKIM and DMARC right and having a domain with a 0 spam score will still land you in the spam directory. It turns out, you need to have a "reputation"? before your email gets accepted into gmail. My head was spinning as to how that reputation will be built if your email just goes straight to spam.
But sure, Linkedin emails are definitively not spam and their dark-patterns at adding you at n+1 emailing list doesn't get them banned from the big (or any?) provider.
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