I doubt cannabis legalization would have much impact on this - the big organized crime control things like the cocaine & opioid trade.

Looking up the assassination you mentioned, it looks like it was perpetuated by cocaine-dealing organized crime.

Also, what is XTC?

Source https://www.drugsinfo.nl/xtc/wat-je-moet-weten-over-xtc

Am very happy to hear this kind of thing is more rare. Not that street users have too much more assurance either way the MDMA they are getting is in fact MDMA, but hopefully thar whatever analogues there are now are a little better than meth or heroin.

Almost all Ecstasy/MDMA outside a pharmaceutical setting is adulterated, usually with other amphetamines. The degree of adulteration varies, and in some cases it may not be very noticeable by the user, but it's incredibly rare to find pure MDMA outside of a pharmaceutical setting.

Methamphetamine is one of the most common adulterants. (This is a bit of a misnomer, because MDMA is itself actually a methamphetamine, but it's not the one most people are referring to when they say "meth").

Ecstasy is almost never pure. While the degree of contamination varies and may not be subjectively noticeable by the user, the vast majority of ecstasy has some degree of adulterants in it, often other amphetamines, and sometimes other substances altogether.

My understanding had always been the two were synonymous.

This is a common misconception. MDMA is often presented as "pure" (often by the people selling it), but in reality, almost all MDMA outside of a pharmaceutical setting is impure. Most MDMA contains some amount of methamphetamine[0], but not necessarily enough to be subjectively identifiable by a user as "meth".

Also, the half-life of MDMA is longer than cocaine, but shorter than methamphetamine.

[0] MDMA is actually a methamphetamine, but it's not the one that people are referring to when they say "meth" colloquially.

Lol, like it weren't the case pretty much everywhere else... Anywhere there is a significant amount of humans, there is "intense organized crime" too; any difference in outcomes is largely due to how authorities decide to address it.

By contrast, there are parts of Italy where 75%+ of businesses are reported paying protection payments to organized crime.

The Netherlands is an interesting case. Despite amphetamine, MDMA, etc. being illegal, The Hague has turned a blind eye to massive industrial production farms in the south. At one point, the Netherlands almost held a monopoly on the world's MDMA production. Rumors of conspiracy suggest it's intentional, but the end result is the same. Many of these drugs are de facto legal, if not de jure. Of course, this was the landscape some decades ago. It's been changing. Mexican cartels are starting to elbow in, and it's been causing "problems". Watching how the government reacts to the evolving ecosystem is going to be intriguing.

As far as being synonyms, people generally differentiate between "ecstasy"/"E" as MDMA in pill form and "molly" as MDMA in powder form.

But maybe that's because I grew up in a time where you can send stuff to a lab to confirm what it is.

XTC aka ecstacy is MDMA + additives like speed or caffeine/whatever.