However, there is a substantial barrier for a programmer to switch careers and become a microbiologist: access to lab equipment. Part of the job of a microbiologist is to work with (usually expensive) scientific equipment to carry out and design procedures for experiments, and it’s hard to study independently without owning a lab space or the equipment. I’ve also found less educational material for self-study online.
Contrast this with self-study in programming. The required equipment is also just a low-end computer, and you don’t need a laboratory environment to develop your skillset. Educational resources (e.g. Automate the Boring Stuff With Python) are also not only widely accessible, but often free.
If you were to ask me, programmers can't learn it because what they are learning is based on complete misunderstanding of organic chemistry (which has not been updated with the modern understanding of physics)... so it is bound to drive anyone who tries to make sense of it crazy. The only way to learn it is to accept all the rules and ALL the exceptions to the rules as the foundation and go from there, which not a lot of people are willing to do.
This sounds like an extraordinary claim, especially since organic chemists work along physical chemists and chemical physicists who presumably have a strong modern understanding of physics. It would be better for an expert to chime in, but I don’t see the incentive where organic chemists would be content to let their field stay out-of-date.
I believe that any good organic chemist must have strength in physical chemistry (both to excel in the field, plus it's typically a degree requirement), and physical chemists are well-informed of quantum mechanics (also typically a degree requirement, with at least an introduction to QM in most introductory chemistry courses in the unit about atomic bonding).
However, it's more plausible to believe the claim (re-interpreted) that many microbiologists don't have a strong foundation in organic chemistry or modern physics. Still, I'm skeptical that those who make it to a tenured professorship can still have these weaknesses, as I'm under the impression that the field is cross-disciplinary with collaborations with biochemists, who can then bring in their stronger background in chemistry (and thus organic chemistry, physical chemistry, and physics). Leading microbiologists (e.g. those tenured at MIT and other top institutions) who influence the field should also have familiarity with these subjects.