Popularity does not imply superiority by technical standards.
1. Agreed. Popularity does not imply superior technology.
2. Conversely, superior technology does not imply popularity. Superior technology loses all the time, especially when going up against a competitor with entrenched network effects. Inferior protocols win. All. The. Time.
3. If you are trying to build a global competitor to fiat, popularity and network effects are incredibly important.
It is unquestionable that Bitcoin has stronger network effects than Bcash, by orders of magnitude.
Further Bcash technology (BCH and SV) is inferior, because its security model is weak. Its security model is weak for a number of reasons, all of which come back to a lack of effective decentralization. Without an effective security model, it is not an attractive store of value. If you are not an effective store of value, you cannot gain network effects.
If you have inferior network effect and inferior technology, then you have a snowballs chance. In the unlikely event that 8MB blocks became essential for survival, community consensus would rapidly coalesce around 8MB blocks, there would be a hard fork and BCH and SV would remain stranded assets. But the reality is that 8MB are completely unnecessary and would make BTC weaker, not stronger. Accordingly no such consensus exists.
I am far more worried about a disruptive innnovation which does away with the need for a blockchain (such as Grin) than I am worried about a Bitcoin carbon copy with a couple of parameter tweaks.