Bullshit. The "thanks" are a small part of the game credits in a AAA.
Death Stranding has 1492 people (1461 developers, 31 thanks) on its credits:
https://www.mobygames.com/game/playstation-4/death-stranding/credits
If you go and watch it you'll see that addition to the typical publishing/QA/localization/marketing/execs/thanks etc of every game, there are a ton of outsourcing companies. Almost always the people of the lead studio are typically around 10% or less of the devs who work on a AAA games.
Regarding Death Stranding team size, as reference:
TLOU2 had 2335 people (2168 developers, 167 thanks)
Cyberpunk 2077 had 3532 people (3156 developers, 376 thanks)
But these 2 were way bigger projects, Death Stranding was more similar in team size to other AAA games like:
Days Gone: 1679 people (1533 developers, 146 thanks)
Returnal: 1344 people (1155 developers, 189 thanks)
Ghost of Tsushima: 1796 people (1697 developers, 99 thanks)
God of War 2018: 1758 people (1698 developers, 60 thanks)
Yes, Kojipro is smaller than ND or CD Project but they only were working on a single game, and even if considering that they were still smaller they could simply outsourced more work to compensate it.