Even more so when that person later loudly proclaims that they never made such a request, even when provided with written proof.
I can of course not say whether the people currently working at Twitter did warn that the recent measures could have such major side effects, but I would not be surprised in the slightest, considering their leadership's mode of operation.
Even as someone who very much detests what Twitter has become over the last few months and in fact did not like Twitter before the acquisition, partly due to short format making nuance impossible, but mostly for the effect Tweets easy embeddability had on reporting (3 Tweets from random people should not serve as the main basis for an article in my opinion), I must say, I feel very sorry for the people forced to work at that company under that management.
If you’ve never had to handle authorization in a particular area, it might have been safe to assume that any 4xx error should have been retried when the code was originally written and someone didn’t write them all out
And even if you do retry, exponential backoff has been the standard for a long time (and is mentioned by the Twitter API documentation as a good solution to 429 responses)