@motivmedia: Yes, technically it could.
Technically the free version can encode all emails as well. You just have to set up the right filters and code them into your theme or MU-plugin. Technically.
The Premium version is significantly more complex. It uses PHP’s output buffers, fail-safe HTML parsing, has custom code for dozens of 3rd party plugins (ACF, WC, Jetpack, etc.) and even obfuscates email addresses in some script tags.
For years I wanted to build the best email protection for WordPress, but the $65 in donations that I received over the last 8 years just didn’t cut it.
I might have built it anyway, but the number of bad reviews and rude AF messages I got killed that desire. Take this thread for example: A 1-star review, without even linking to a better plugin that people could use.
I wanted to serve people who want the best product possible and value customer service.
I continuously work on improving the Premium version and every couple of weeks features (like for example automatic cache flushing in v1.0.15) trickle into the free version.
So despite palatin8’s conclusion, the free version is getting more love it has in years. I also never removed any features or limited the free version in any way.