There is a post about using Google Tag Manager for SEO experiments and if Google is able to pick up on the title tags, meta changes, etc with using Google Tag Manager. It is a pretty interesting blog post and covers the tests well. Although it is somewhat fascinating, Google's John Mueller doesn't recommend you use Google Tag Manager for SEO purposes.
John said "I'd avoid that if at all possible too." "Getting SEO reasonably right is hard enough without adding a layer of 'unpredictability" on top," he explained.
Martijn Scheijbeler gave a bit more of a detailed explanation on the issues with taking this approach:
Yeah, I'd avoid that if at all possible too. Getting SEO reasonably right is hard enough without adding a layer of 'unpredictability" on top.— John â.o(â§â-½â¦)o.â (@JohnMu) December 27, 2017
So if you want to have fun on a test site, sure, go at it. But for sites you don't want to test or risk, I'd stay away.
Forum discussion at Twitter.