Does Google Tag Manager could or should be used to change content in a page, like title, keywords or description?
Is possible, feasible or even recommended (if possible), to change the title or the keywords of a page using Google Tag Manager?
seo;google;ajax;google tag manager;crawlable ajax
Google is improving it's ability to read javascript rendered pages. However, it's not to a point you can rely on it for inserting critical headers. Here is one such article on researching this possibility. For now, you need to have the important information embedded into the HTML when it's served. There is also the chance that javascript rendered changes in content will be seen as cloaking - although it is commonly used for A/B testing.