Wheel size for heavier rider, larger vs smaller I am a heavier rider, whilst still reducing, I am over 120kg or 260lb.

I have broken many spokes on the rear of my 26er sub-$500 mountain bike. Broken at the elbow. There could be many factors for this from being a cheaper bike to not maintaining the spokes. This is just background for this question.

I am going to purchase a new hard tail bike. 

Given a choice of the same bike brand and model coming in either 27.5 or 29 where the wheel is also the same brand and model. Which is going to be a stronger wheel and less likely to break a spoke and last longer?
I've heard before that a smaller wheel is actually stronger, and this site states the following.


  Because a 26-inch wheel has a smaller circumference than a larger 700c wheel, the rim is structurally stronger and resists deformation from impact. Wheels that are 26 inches excelled at handling hard drop-offs and even crashes without losing their true.


The way I understand it is that a 26 inch wheel is shorter, and therefore has a shorter lever arm when stressing the spokes. Imagine you had an enormous wheel. Because it's so big, you'd need very little force along the rim of the tire to deform the rim. Now imagine a smaller 20 inch or even smaller wheel. You would required a lot of force to deform the rim because it's being applied closer to the hub.  Also, assuming the same number of spokes, the smaller rim will have the spokes closer together on the rim.

I was able to find a couple other sites that agree that smaller wheels are stronger.

700c vs 26inch Wheel Size for Touring

This site states, among other information


  Not everyone can afford the highest quality wheel and tyre parts. If
  this is you, a 26inch wheel will offer more strength for your buck.


Wheel size facts Part 1.... Dimensions, Weight and Strength


  If comparing like to like wheel builds (same rims, hubs etc), smaller
  wheels will always inherently be stronger than larger wheels. This is
  due to wider gaps between spoke eyelets and poorer spoke triangulation
  etc. So strength to weight ratio is something that will always be won
  by smaller wheels.