IRCC extended an ITA because the applicant filled up the form and said that they have 3 years of work experience. I don't see anything wrong with that? I believe it's the applicant's responsibility to make sure everything in the form and whatever they are submitting is accurate and true. (The applicant is even reminded that when they finalize their EE profile submission).
That's very anecdotal evidence.
It literally says it here:
https://www.canada.ca/en/immigration-refugees-citizenship/services/immigrate-canada/express-entry/eligibility/federal-skilled-workers.html on how work experience is calculated.
If an applicant slipped through the cracks on this requirement, then they got lucky. If the applicant was called out then they can't contest anything because they, in fact, did not have 3 years of work experience imo.