I have rarely been accused of being succinct ).If only I could say such things so directly and succinctly.
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In particular, @Bs65 emphasizing "the residency obligation of 2 years out of every 5 is a generous obligation to meet," recognizes the dominant outside parameter for evaluating whether H&C reasons justify keeping PR status. Regarding which you added the exclamation mark, noting that EVEN IF there is a formal policy, it will most likely offer only limited relief.
I agree with your points overall, was only perhaps putting a slightly different emphasis.
Mainly, that I would not suggest anyone rely on a 'formal' policy being issued, or plan on the basis that such a hypothetical policy would cover their specific circumstances, particularly down the road.
Sure, there will likely be some leniency (whether formalised or not) - as in many cases the travel restrictions themselves will be a genuine H&C consideration (especially if they amount to a case where someone simply could not travel, e.g. no flights in or out of the foreign country, and travelled when they could). That doesn't mean this particular H&C consideration will be sufficient on its own - details of individual cases matter.
Legal advisors noting 'there is no formal policy' are correct and no-one should rely upon such a policy or leniency being granted (leniency generally being 'more tolerant than expected or required'), given the existing requirements are rather generous.
If there is such a policy in future, it can be evaluated at that time.