If I'm interrupted during checks, or there's a delay and perhaps it's so hot as to open the canopy again, I do part of the checks again,
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Good practice.
As an aerial cameraman and former pilot I can attest that distractions leading to mission creep or outright mishandling is very common, even for 10000 hour pilots.
Whilst the effects of human factors in aviation is well known, my personal experience is that specific training in regard to distraction would be beneficial to new pilots.
So whilst eliminating a distraction such as a camera, from a student flight is one approach, another is to train and practice for distractions.
It would be quite stimulating for instructors to setup preflight and inflight distractions that could include smartphone and cameras as the protagonists.
Mjb