Mojave's Dark mode is much better IMO simply because on the mac they allow extensions like dark reader on Safari and it works almost perfectly. Everything is dark on my mac. I don't care for apps like news on my Mac because its look like an iOS app but I do care on iOS and that's my point. I know that third party apps need time, but for first party apps, Apple should force a dark theme in apps like news, mails, dark keyboard everywhere and at least, give an experimental option for Safari to make website dark. Extensions and browser who gives real dark mode is very popular and they have demand for it.
The "brand identity" thing is BS IMO. we don't demand to modify logos and banners, but I think a white or dark background should be the user's choice. In early 2000's, website had way much variety than now but since the 2010-11's, almost 90% of all the internet became all in white, including operating system like iOS and Android. Thats why demands for a dark mode became so popular because companies almost forced everyone to accept one design.
I know some people will say our brain is programmed to read better with white background/black text, but the fact is many people prefer a darker background and I dont think its too much to ask. In early iOS and Android era, there was no demand at all for this mode and you know why? Its because at that time the designs was way more balanced and not just offer extremely bright white everywhere they can.