Option Tree - Wordpress

Is it acceptable to integrate the OPTION TREE plugin for custom options when building a Wordpress theme for the market place?

i just got soft rejected for not including option tree as a plugin, so obviously yes, and it seems a must

I didn’t get a rejection message last month on my latest item. I think they just decided to make a change again

Last week there were no issues with inlcuding it in theme mode, you just need to integrate it properly.

What ? Isn’t OPTION TREE a old plugin ?

Isn’t WP Customizer the standard now ?