Oh I have seen this story and was the one who caused this story when I was younger.
In a lot of cases the "new guy" thinks its an easy software and does it on his free time and thinks he did a great job.
In reality the specs are never 100% done correctly. The "new guy" misses some edge cases everybody but him knew because its just company knowledge. A lot of info in the specs was missing since they are not complete and so on.
This over the weekend never works in the long run. The ORM worked for all the happy path and written down cases but then you have cases were the ORM just is not good enough or fast. So you start to add strange code to work around the ORM. The same for the web framework or the validation lib.
To me the author of this comment sounds like the typical "Freelancer" coming in into a company knowing everything better then all the people and then leaving after a few months and now everybody else has to deal with his code.
It swings both ways though. I've seen plenty of older engineers dismiss the "new guys" effort and claim that everything had to be custom written, because there's no way a common framework like Django could cover their use case. The same type of engineer has never once worked with a common framework though, so they don't know what's included nowadays.
Turns out it's a lot easier to build on top of a common framework than do everything from scratch.
Sure I had an older dev do bit masking for a list of 3 options in javascript because he was used to old terminals.
Its something different coming in and changing things here and there but rewriting the hole thing on a weekend is something different.
I was very impressed with vBulletin’s use of bitmasking for permissions (of which there were many possible combinations) when I first encountered it.
Would love an excuse to use it, but one has not come up in like 15 years since, hah.
I think it's safe to say that ORM in Django is, in fact, better in all possible ways than an ORM someone at some company just wrote. Including speed and handling edge cases.
We only know what OP wrote and he doesn't sell himself as a genius but as someone who was competing with really, really bad ideas.