
To ship any Eclipse packages with an outdated Jetty or without the Help system pre-installed would be a major detriment.

This is a difference compared to Java 7 which just updated the libraries but not the language. Java 8 introduces some interesting new language features which some contributors can’t wait to use.Furthermore, all major versions of Java before 8 are officially end-of-life as of April, 2015 they will no longer receive public updates, making them security risks.By the time 4.6/Neon ships, Java 8 will be 2 years old (so no one can call that "bleeding edge").In terms of security fixes, it’s safer than Java 7 (for example, TLS v1.2 is only enabled in Java 8 by default). Java 8 is available today on all major Platforms (including Linux-ARM for example) and by multiple JRE vendors.

In the end, a few hard requirements to make useful packages tipped the scales. There was open discussion in the Platform and EPP communities about this decision. As of Eclipse Platform 4.6, and the Neon release, a Java 8 (or later) JRE or JDK is required to run Eclipse.
