I don't like to be overly negative, especially when a company/team is being transparent about what they're doing and giving insight into their engineering practices - but has anyone else's estimation of Plaid's engineering team just gone down the toilet? This blog post gives me the impression that either Plaid is filled with either junior or incompetent engineers - to scale to 4k containers serving 1 request each for…
This comment says more about you than it does about Plaid. Their "insane" design met business requirements successfully enough to grow them into a multi-billion dollar company. Did you consider the likely (and more charitable) explanation that they were aware their design was "bad", but had higher priorities until now? If I were you, I'd be pulling your comment before it harms your reputation any further. :)
I think marketing and VC valuations grew them into a multi-billion dollar company; whether they remain so, to a large part relies on how fast they burn through VC cash - so, not looking too good on that front...
No even half-way competent engineer would come up with such a complex, unperformant solution to a simple problem - I think a higher priority should be hiring engineers who actually have a clue what they're doing.
As for meeting business requirements... while this might have worked for a while, it was plainly not a good way to meet them, and given Plaid are in the banking sector, really doesn't bode well for the future (I'm having flashforwards already to security breaches, plaintext passwords etc...).