This might be judged more of a discussion than a question that can be answered, but bear with me.
I began my epub journey with a series of InDesign tutorials that instructed me to choose 3.0 as the default setting. I quickly gave up on InDesign and began using Sigil, but I continued using 3.0 as my default.
Then I ran into some heated debates regarding the relative merits of Epub 2.0 and 3.0. Some people claim Epub 2.0 is readable in far more devices, making 3.0 a lousy choice. However, others claim that there's no significant difference, except that certain FEATURES supported by 3.0 won't display in all devices.
So here's my question: Is the above statement true?
I'm aware that Epub 3.0 books are being produced and sold by Amazon, iBooks and others. I've just run into people that insist that 2.0 is really the only way to go.