Wrong.
From the first study:
“Since the pre-therapy low testosterone levels were independent of the aetiology of impotence, we hypothesize that this hormonal pattern is related to the loss of sexual activity, as demonstrated by its normalization with the resumption of coital activity after different therapies. The corollary is that sexual activity may feed itself throughout the increase in testosterone levels.”
About the second, which can be a bit hard to understand, well just read the title
Sexual inactivity results in reversible reduction of LH bioavailability
The 3d article I posted has nothing to do with people wiht ED.
Those who believe that abstinence has such great effects have a religious bias, a way or another, and the supposed ‘benefits’ they notice are just a placebo effect. There is little or not scientific evidence : actually, it can be argued that masturbating and sex are beneficial, since the ‘use or lose it’ seems to be a universal rule.
As counterproof, I’ve noticed that all the guys who claim benefits from abstinence do have religious or mistic beliefs of some sort - very few of them, if any, are atheists/agnostics.