Ask anyone that has a large collection of notes with tags and dozens of folders, there is no graceful way to export your data in a usable format. Attachments are exported with their original file names (not the note name) and all structure is lost (tags and folder are lost).
I as one of the people that asked for Evernote to make a better export feature to ensure they met their own portability commitment. I wasn't sure how it should work, but knew it needed something better.
As you added more and more notes, this feature became more important and the lack of it became a glaring issue. As much as they say you can export in HTML, the exported data is useless.
So they failed to meet their own 3 rules of data protection.
No Markdown Support
As a technical Evernote user, I was part of their forums, UserVoice feature request system and always answered their user surveys. A feature I have wanted for years was Markdown formatting support (which would improve note compatibility). Their standard response was always that this was not part of their road-map. I wasn't the only one clamoring for Markdown support. Their forums listed thousands of users asking for it.
Unfortunately Evernote was clearly not interested.
Less consumer more business
In an interview with The Verge, Chris mentions the wants a more balanced customer base (less consumer and more corporate. This clearly shows in the steps they have taken and ancillary services they have killed.
Consumer services have been killed (Food, Flash Cards, etc) while corporate ones have been maintained (Evernote Work Chat a slack competitor and Presentation mode a Powerpoint competitor).
Changing competitive landscape
As Evernote continues to squeeze its free tier customers and makes paid tiers more expensive, it's primary competitor, Microsoft OneNote, has gone free for everyone on every platform. Additionally Google has its Keep/Google Docs combo and Apple its's Pages/Apple Notes combo. All of its chief competitors are offering more and more functions for free.
Others like Dropbox have launched services like Dropbox paper offering their existing subscribers cool new Evernote competing features.
When I started using Evernote, it was the defacto standard integration partner for every app or service that I used. Almost every app I had on my Windows, Mac, Android, iPhone or iPad integrated with Evernote. As Evernote alienates its customers and more competitors enter the market, this is becoming less and less true. There was a huge benefit to knowing everything you had would work with Evernote, as this slowly disappears, that advantage also disappears.
The Best Evernote Alternative
Having tested dozens of services, there isn't a really good alternative an Evernote power user will like but you have to accept this reality and move on. Evernote has clearly shown disdain for its consumer users and so the search for an alternative is ongoing.
The closest to Evernote has been Microsoft OneNote. OneNote is now free for everyone, getting more polished and feature rich with every update and they are clearly targeting Evernote users. It will definitely take some getting use to but it is a close enough alternative that most users will be extremely satisfied.