Hi, I know this video / hangout about there is a question about content after read more button / tab
The advice is, that if content is important don't put it behind tab / read more button. Google can see this content as hidden or less important, and will try to ignore it.
By using the word "try" you can ask yourself, is Google abled to ignore this content.. i don't know.
Anyway if you look at the importance of the content; i'll say always show important content to your clients, do not hide it behind tabs and or read more buttons.
grtz, Leonie