TPM = Trusted Platform Module. Trusted is an adjective modifying platform. The business case is that software should not run on untrusted platforms because hardware can always attack software. So, the promise is that TPM will allow software to guarantee* to users that the hardware is not malicious.
* as much as one can guarantee anything in tech
From my perspective TPM is mostly about compliance with security directives. Actual security engineers would realize the TPM's security provided is about as far as you can throw it. You have no idea who designed the thing, who manufactured it, or who swapped it out while it was in shipping to you.
Wait, what? In most cases you 100% know who designed and manufactured it. Regarding "swapping out" a TPM, how do you do that for fTPMs or TPMs that are on the same die as the CPU? Come up with a perfect replica AMD CPU with a bugged TPM? Desolder the original CPU and put the replica in?
It's painfully obvious nowadays that openssl was written by the NSA (or equivalent state level entity) via intermediaries deliberately adding subtle but significant vulnerabilities.
Let me propose this metaphor: you buy a front door to your house. For some reason I (the door vendor) include a complete lockset. I tell you that the lockset is totally secure. I offer you volumes of academic research and attestations that this is true. But there is no practical means by which you can establish the security of that lockset.
Do you believe that no one else can open your front door?
The problem is that your lack of context and perspective on this fairly simple, easily-falsified theory calls all of your opinions into question.
A more nuanced conspiracy theorist would say "if you look at PR's to openssl that contributed later-discovered security issues, 70% were from first-time contributors who never went on to submit any other PR's". And I'd be like "wow, that's suggestive of a coordinated action", and we could dig into it.
But "the NSA wrote openssl" is as factually, demonstrably wrong as saying "the NSA builds every door lock that's for sale at Home Depot". It's too big of a conspiracy, to inefficient for the supposed state goals, and too easy to falsify by just looking at a couple of examples.
You might for example, just outright buy out the cryptography solution providers:
https://en.wikipedia.org/wiki/Crypto_AG
Money is a relatively simply mechanism to achieve an end goal. Much safer than for example, torturing someone or beating them with a wrench.
"Plug this chip that says made in China into your mainboard, for security reasons, to continue." is not really emitting trust or confidence in any way.
I'm sure 30 other chips made in china on same board are entirely fine
All wrong, as others have pointed out. As for the last of the above, if the OEM includes (as they should) platform certificates for the TPM, then the TPM cannot have been swapped out while in transit w/o the OEM helping the attacker. For example, Dell includes platform certificates binding the TPM.