I would normally not touch campaigns from people like the FSF and EFF, but in this case, I have something to say that is not a simple series of angry growls and the desire to set fire to office buildings.
Occupy Flash (I wish I were making this name up) is an apparent movement to push people towards uninstalling flash entirely, removing it as an option for web developers and web designers to use. Their reasoning is as follows, from their manifesto:
Flash Player is dead. Its time has passed. It's buggy. It crashes a lot. It requires constant security updates. It doesn't work on most mobile devices. It's a fossil, left over from the era of closed standards and unilateral corporate control of web technology. Websites that rely on Flash present a completely inconsistent (and often unusable) experience for fast-growing percentage of the users who don't use a desktop browser. It introduces some scary security and privacy issues by way of Flash cookies.
Flash makes the web less accessible. At this point, it's holding back the web.
In many ways, this is absolutely true. Flash is a rather painful plugin that has many security problems. However, then you scroll down, and see this:
The only way to truly force the web to embrace modern open standards is to invalidate old technology.
In my eyes, this is not only hypocritical, but entirely against the idea of an open web. In a time where many developers state they want an open web while pushing for the idea that "everyone should use Chrome," I am utterly convinced that people—including web developers—do not know what the term open web actually means.
The open web is one where people have choice, and people make choices. Where you can make websites that have DRM on elements, paywalls that block content, and plugins like Flash and Java. Where you can choose to use a browser that has features that others do not, such as Kmeleon, Rekonq, and Midori. Not where you force your choices on others.
There are still many people out there who think the only way to build a website is to use a bunch of JavaScript frameworks, like node.js and Angular. Some of them even try to force those beliefs on others.
The other problem is that HTML5 is not ready for the regular user to create things like animation, at least not easily.
Adobe created the Flash suite, which made it almost trivial to create animations and games with timed audio and video. The suite itself was designed to be user friendly for creators, not just developers. The plug-in was standardized in a way that would let you write once and run anywhere, and all you require is a single plug-in that can be disabled if you do not want to use it.
There are no applications or suites which would make it easy to do the same in HTML5. You need CSS, HTML, JavaScript, possibly SVG and other pieces. For 3D animations, you need WebGL. And all of this is assuming that someone is running a browser which will support everything you need, and/or has JavaScript enabled. Unlike Flash, you can only really disable flash, as HTML5 audio, video, and canvas elements cannot be disabled at all, or at least not easily.
As has been pointed out to me, unlike Flash, HTML5 offers an easy way to create such a tool. However, I will also point to KompoZer and BlueGriffon, two web design/development tools to make it easy for users to make websites. Neither of these tools have been updated in a long time, and are effectively vaporware at this point. No one is stepping up to make anything similar, as many people in that sector believe you should just encourage others a developer, rather than saying "people should not become developers just to display art."
People hear about the problems with Flash, and I will not argue that there are major problems with the platform, but that seems to be all they hear about now. They do not hear about the fact that it helped someone jump-start their game development dreams, or to help create a great animation that others could enjoy. They do not hear about the fact that, if someone were to find a vulnerability in HTML5 audio or video, that there is no way to easily stop such elements from loading without using something like an ad blocker, and there is no way to disable audio or video on a per-site basis.
With Flash, you do have the option to easily set click-to-run on Firefox and Chrome (and others), or to even disable the plug-in entirely. Firefox does so automatically if it is found to be vulnerable, but I would argue that doing so is very anti-user, as they are not making that choice, Mozilla is making it for them (treating all users as idiots, rather than as people). Hijacking someone's browser "for their safety" is still hiacking their browser. Likewise, taking someone's choice away in the name of "advancing a standard" is only going to hurt users in the long run.
Honestly, the plug-in architecture, despite being vulnerable in many cases, at least gave users a way to stop using bad plug-ins. It also offered a way to create your own plug-ins for others to use, rather than forcing a single monopolistic standard that cannot be disabled.
Users can simply use older browsers, avoid Chrome, and tell developers to "go away" in the end. That is their choice, and web developers have no say in the matter. The open web will remain open, despite what so many do to go against that.
Then again, it is not like many web developers will even notice. They are too busy trying to impress each other with their "framework of the second".