I made an earlier post regarding the 430EXIII-RT and I should have also added that one of it's features is that you can fully control it from the cameras menu system even via the EVF. This is about the only way I use the thing. I don't think you can do this with the Godox, etc. but they have other benefits that others have pointed out.
As has been noted, the Godox speedlights can be controlled by the camera menus, as can Yongnuo's RT clone and 500-series and later eTTL-II models. I'm pretty sure Sigma, Metz, Nissin for-Canon models do, too. This is pretty common with current 3rd-party flash models. But some of the more esoteric features may be missing.
Granted, Canon service and warranty repair have absolutely no competition from the Godox side, where you're relying on a retailer to cover the warranty period with replacements. If you want CPL-like service, Godox ain't it. OTOH, if you're only a hobbyist shooter who wants to play Strobist for not much cash, it can be just the ticket.
OEM Canon speedlights also have a few features you won't find on the Godox ones: Ext.M/Ext.A [autothyristor], and TTL [film] metering modes vs. eTTL-II switching tends not to be available, only Yongnuo has replicated the flash-as-shutter-remote functionality, and Godox uses two-digit ID codes, not four-digit, and doesn't do a radio channel graph. You also can't do remote wake-up with Godox, which is a serious PITA they really need to fix. Also, OEM flashes tend to have better head rotation/locking, better AF-assist and more accurate/consistent TTL performance. But the 3rd-parties are generally good enough, if not identical.
Where Godox has Canon beat is, however, is that they have li-on versions of all their AA-powered speedlights, do 2nd-curtain over radio, the "Pro" transmitters allow for TTL locking (being able to convert a TTL-set power level to the equivalent M power setting to lock the flash exposure), cross-brand TTL/HSS support for five other brands (Nikon, Sony, Fuji, Olympus/Panasonic, and Pentax), and the ability to remotely control/integrate studio strobes (both battery-powered and A/C powered). Also all Godox speedlights have S1/S2 "dumb" optical slave modes. The TT685-C and V860II-C, in addition, do master/slave in Canon's smart optical system.
Godox also make a $60 single-pin radio-controlled speedlight, the TT600, which allows for remote M group/power control and HSS as a radio slave. Handy, if you want to put together a four- or five-light off-camera setup on the cheap, or you may possibly be putting a flash in a situation where it could be destroyed [say testing an underwater housing or whether you can light with a drone and you might be reluctant to risk a 600EX-RT]
.
It's the current weapon-of-choice for the Strobist.
If your main usage for a speedlight is off-camera lighting, and you want expansion options that include larger barebulb flashes or studio strobes, then Godox is a better choice than Canon's RT options which are speedlight-only, or force you to much more expensive still-third-party options for studio strobes (e.g., Jinbei TR strobes or Phottix Indra). And, as a hobbyist without the need for backup gear, Godox can be a no-brainer. Particularly if you shoot more than one system, since Canon RT speedlights are only TTL/HSS with Canon cameras.
If your main usage for a speedlight is on-camera bounce for event shooting, then it may be that an OEM speedlight makes more sense, with the exception of whether you need the longer life of the li-on battery in a Godox V1 or V860II. A lot of all-day event (wedding) shooters do, and prefer the packs to drowning in AAs. Each li-on pack has 2.7x the capacity of a set of 4xAAs, so basically one li-on pack = 12xAAs; and it's kind of the equivalent of having an 8xAA external battery pack built in.
