Some of this seems a bit off.
You should know poppers are one of the nitrites of the alkyl nitrite family, not just isobutyl. If these "problems" are solely with isobutyl nitrite, then your problem should be with governments (the US federal government specifically) preventing individual responsibility and choice by prohibiting drugs.
I don't think it matters specifically why/how it helps guys take cock, just that it does. I've felt my boyfriend's hole relax after huffing, and he has told me similar to an analgesic, the pain is muted and all he feels is pressure.
I don't know about MDMA, but it is pretty well known by a majority of people who use poppers that Viagra and other meds that lowers blood pressure, as well as those who have low blood pressure should be cautious with popper use, if not avoid them completely.
Again, like #1, I think people don't specifically care how or why it happens, just that these are the effects that are experienced, and these effects are sought because they allegedly enhance sex.
You've been pretty consistent about chemical names and perhaps it's a mistype, but you wrote alkyl nitrate. On the slim chance you didn't mistype, alkyl nitrites and alkyl nitrates are two completely different chemicals that cannot be compared. And if you did mistype, could you please link to the studies/reports where these adverse effects are seen?
This really comes off as judgmental. If poppers are not your cup of tea, then don't use them. Some people think they are enjoyable and add something to their experience. I don't think people think poppers, or any drug, are completely harmless; even as someone who thinks drugs are "harmless" provided responsible use, damage still may occur. It is up to the individual to determine whether or not it is worth the (risk of) damage for the trade offs. If you could link to the source I requested in the response to #4, that would be great. That would be of great interest to many people here.
I'm all for educating people of the risks and dangers of drugs, but this entire post feels very preachy.