Today, everything destined for the web is best in sRGB. Sure that may change, but it won't next week, month or even year probably.
Why? Because most (if not all) displays are set to use sRGB by default from the factory and 95% of users don't know how to alter it and in all probability even if they do... don't care to alter it -- especially merely for your content.
sRGB is as close as you'll ever get to controlling color over the web.
P3 may show better color to you or perhaps better in Google browsers. But someone viewing the image in another web browser is going to be using sRGB - and different browsers will render differently. So, you are introducing a level of complexity to how the image displays, and therefore also introducing the possibly of poor color matching. sRGB has become, for the most part, universal.
Even if P3 becomes standard, it'll be years before it is as prevalent as sRGB. So unless you plan on creating images to be the same forever, you'll most likely be updating things prior to P3 becoming more standard. That article was written in March of this year.. it may be 2+ more years before operating systems and display manufacturers change, if they change.
For the record, the same conundrum was presented when Adobe RGB appeared on the scene... and years later, today, sRGB is still standard for content destined for the web for the same reasons I've outlined above.