[JoshTriplett]

How many projects do browser detection and block everything that isn't Chrome? A tiny fraction of websites do that.

It's absolutely a concern, just as sites relying on WEI is a concern. But it seems unlikely that sites will intentionally choose to exclude a non-trivial portion of their visitors.

If you want to make it even less likely, though, this is a great time to switch to Firefox (for its independence, as a browser not based on the Chrome engine at all).