The fitness industry is scandalous and makes this situation worse by offering all sorts of gimmicks and promises of great results for little or no effort. The megahype muscle magazines are the worst example. The information found in them is not only fraudulent but may even be harmful to non-drug users. If you train naturally, there is no magic formula. Any results that anyone ever got had to follow that formula, not miracles or gimmicks, just hard work, nutritious food, and plenty of rest.
Intensity is defined as the amount of work done per unit of time.
It doesn't matter if you do pyramids, reverse pyramids, or straight sets, superslow or superfast. It doesn't matter if you go 2 seconds up and 4 seconds down or 10 seconds up and 5 seconds down. There is no ideal method or ideal range of reps, sets, etc. The mode and methods are not universal so you should experiment, but focus on the basic movements. Find the methods you like, but always stick to the absolute rule.