The specific anecdote may have been fabricated, but the principle is sound. An example is the marshmallow problem[1], where a group is given some materials and is asked to build, under time pressure, the tallest tower they can with a marshmallow on top. Adults generally fare poorly because they don't experiment enough, building a tall tower and placing a marshmallow on the top as time is running out, only to have the tower collapse under the newly introduced weight. Children often do much better because they start with small, simple structures and iterate quickly.
I don't know if that is really the same principle as the pottery anecdote however, it's not about experimenting but a narrative enforcing the concept 'practice makes perfect', related I suppose but not the same.
And anyway the pottery principle is not really sound either - I can suppose that the group tasked with producing a pot a day produces a better pot at the end than the group that was given a long time, but let us assume pot-makers both extremely skilled - one is tasked with making a pot a day for 30 days, the other making a pot in 30 days - which pot under those conditions will be better? The pottery principle is only interesting in explaining how to build a skill, but does not have anything to say about what to expect from those who have already mastered a skill.
You can make the same very bad $creative_product every day indefinitely without improving at all.
Which is why there has to be at least some assessment and feedback. That's the big benefit of having a teacher, mentor, and/or the feedback of peers, customers, or an audience.
If you have a mediocre talent they'll steer you towards making the most of it. If you have exceptional talent their feedback may be wrong or misleading, but it should at least make you think more deeply about your relationship with what you're doing.
You can't assess your own work realistically unless you have something to compare it with, and the critical skills to understand which features matter.
And in relation to programming, entrepreneurship, etc. getting basic experience doing "the full pipline" matters. Releasing _anything_ gives you experience in preparing _something_ for release, whereas if you tried making a perfect program you would miss out on what matters early on for an eventual release and be able to coordinate those for your next product.
There have also been discussion about the same thing happening in music and science. That is, the people who produce the best work also produce the most work, and a lot of that work is bad. But some of it is very, very good.
[1] https://www.ted.com/talks/tom_wujec_build_a_tower?language=e...