You are correct that their CTO has submitted 16 posts this week (not all of them from their own blog), but I don't see the harm in that: less than half of them attract any comments at all and quickly slip beneath the waves.
Also, to be fair, it has been an unusually busy week, as they had a "Crypto Week" during which they announced something genuinely interesting each day, and their 8th birthday was a fair excuse for a navel-gazing post.
Aside from 1(techcrunch) they are all just posts of their own blog. I would call 15 submissions about your company in 7 days excessive.
If more people start doing this the danger is that HN gets reduced to just another marketing channel. I think that's a reasonable concern.
The majority of these posts tend to go into deep technological explanations, making it a good fit.