Ecstacy is known to cause the body temperature to rise. People write it off as just being the club, alcohol, etc. For some people, the temperature becomes high enough to cause death.

This doesn't have anything to do with drug purity and has everything to do with the effects of the drug itself.

Millions of people take MDMA every weekend. Deaths from pure MDMA have happened, but they are extremely rare. It's important to think about risk from a statistical point of view. Everything has risks.

To be fair, I think that you are more likely to get a bad batch of a "party drug" like ecstacy than LSD. Though I can't really talk from experience here, it would seem (to me) that party drugs are more popular and would attract more people to cut corners to turn a quick buck.

Pure mdma would not kill anyone at a normal dose. Test your pills everyone!

Test your pills? How? Anyone can do it?

In fact, yes: there are nonprofits that distribute testing kits for recreational drugs (https://en.wikipedia.org/wiki/Pill_testing).