And that's the end of your hardware innovations. Be happy with what you have for the next 5 -10 years. Like having a high performance PC without a fan. Try to find one. The traditional 5D user base has evaporated. Cameras are niche devices already as it is. Not even smartphones are manufactured without a video option.
I don't think that's a reasonable comparison. What proportion of high-end PCs are used in the rain? High humidity environments? Blowing sand? I don't have the answer, but I can promise you this: if high-end PCs had to be commonly used in direct contact with water, they'd be weatherproofed in one manner or another to prevent damage. How many wedding photographers/journalists/sports photographers/landscape or wildlife photographers tell their clients they can't do a job if it's raining? Not shooting in the rain isn't always an option depending on your business.
For me, weather sealing is more important than further innovation for the next 5-10 years, so if no innovation is the cost, I can make peace with that. With that said, weather sealing isn't new on cameras and we've had plenty of innovation over the last 5-10 years. I kind of doubt you can't have one without losing other.
I doubt any of us have the actual data to prove that the traditional 5D user is gone and obviously Canon doesn't think that if they made a camera to service the market. In fact, most camera manufacturers seem to be diving
into the traditional 5D market of full frame, high quality, stills-first cameras with weather sealing. I don't discount that a lot of people rely on video from stills cameras; that's certainly true considering that several of the manufacturers with 5D-style weather-sealed bodies also make actively cooled bodies with a video focus. That's a good thing - it lets the people who need that video performance sacrifice their weather sealing, and people who need weather sealing sacrifice their video performance. There is no one size fits all, and that's ok.