Google: There are no exceptions for speed tests including our own products
Google's John Mueller said on Twitter that it doesn't matter what is slowing down your pages, if your pages are slow, they are slow. Therefore, if it's a Google product, such as Google Analytics, Google Tag Manager, AdSense, Ad Manager or another Google product that is slowing down your page, find a way to implement it so that it doesn't slow down the page.
If you know that you've integrated a Google product that slows down your pages and you know that it's impacting the speed of your site, then there's a problem. Google doesn't give you a pass, just like your users, and therefore conversions, don't give you a pass, because it's a Google product that slows down your page load time.
John said on TwitterHe says, "On the face of it, there is no exception for speed testing when using our products and services - they can slow down your site like anything else. Sometimes there are integration ways that limit the slowdown, but ultimately it's up to you."
Off the top of my head, there are no exceptions for speed testing when using our products and services - they can slow down your site just like anything else. Sometimes there are integration ways to limit the slowdown, but ultimately it's up to you.
- John (@JohnMu) February 12, 2020
Will Google products slow down your pages to the point of hurting your rankings? I doubt it but still, you want your pages to be super fast for your conversion goals.