If the light is right, your feed it’s too much if you taco.
There can be many reasons why the plants may not be able to handle a certain light intensity but the tacoing from heat and light stress is always a response to too much light/heat for the plant. Factors like genetics, nutrients, ph, temp, humidity, wind, co2, o2 etc etc etc will reduce the efficiency of photosynthetic rates. In all cases resuce light until its is corrected.
Pretty much the only hard rule i can think of when it comes to cannabis. No matter the issue reduce light until corrected.
Now there is an influence we havent yet discussed that and thats very high transpiration rates make the plants more turgid and the V shape may be slightly more pronounced but thats a good thing. So as i say a slight V is good but folded like a taco is too much. You get the feel for it pretty quickly once you pay attention