They don't what? Benefit training, recovery and strength gains?
Your mental gymnastics to avoid the fact that they do makes it come across as if you use them, but don't want to accept that they're part of the reason why you're seeing results
Yes they do benefit training, they help you recover and therefore you can increase your time pushing yourself, which in turn makes you stronger, or more agile. But no PED will actually make you more agile, or stronger. For that to happen, you need to put in the work.
To put it simply, for exemple, if you're used to squatting 2x/week, 100kg for 3x3, if you take PEDs and you keep squatting 2x/week, 100kg, for 3x3, then you're not going to magically get stronger.
What PEDs will do is allow you to increase the amount of volume, which then makes you stronger, assuming you keep pushing yourself.
As another example, if you sit on the couch and do nothing all day, if you take PEDs, you're not going to suddenly become stronger/fitter.
If you don't push yourself, increase training load/volume/frequency, eat for the required objective, etc, you will get absolutely nothing from taking PEDs.