There is a rumor via CR where they say that Canon might introduce a new Canon EOS-R 100MP camera as early in 2020. This is a kind of very vague rumor that will obviously become true as the Megapixel race will never stop.
So rumor or not, we know this is going not only going to happen with Canon but also with Nikon, Sony and Panasonic future FF cameras too.
An example: I bet the Sony A7rIV or A9r which is likely to come sometimes in late 2019 and early 2020 or 2021 (LOL) will have a close to 100MP sensor too. Sony officially said their FE lenses can resolve 100MP resolution.