That wouldn’t be actually true, as themes do not offer such functionality by design. A theme’s job is to stylise and provide a solid foundation for your website.
It is a plugin’s job to offer SEO enhancements, as many of the options on the WordPress store do. I’m actually curious to see where did you read that we are not compatible with these plugins. That is most definitely not true. We are compatible with most of the popular choices on the WordPress store. 😉
However, we will not be able to offer support for installing and/or configuring any third party plugin.