This is a very good point.Different photographers have different needs. Everything Jeff Cable said made perfect sense from the point of view of a successful (and reasonably wealthy) professional photographer.
Professional sports and wildlife photographers will usually have access to ultra-expensive long primes such as 600mm F4 or 800mm F5.6. Combined with their need to process and transmit images rapidly, it makes sense the have a relatively low MP camera.
But for most amateurs, unless they are very wealthy, the reality is that they can’t afford these long primes - they are generally using shorter and more affordable lenses such as 100-400mm zooms, which necessitate the need for heavier cropping. Also amateurs in most cases just don’t have the close access that a press pass provides. So many would argue that more MP and more cropping is often the only solution.
General advice is that it is better to spend money on lenses than a camera.
At a certain point spending more on a camera is far more affordable.
Although an M6 Mark II would offer more reach than the R5 at a given resolution.