Is the biggest risk to xmr a community launched zcash clone without the premine and founder tax, like how xmr began?
If I am honest, not many here are interested into Zcash so I do not see it even competing with XMR. Bear in mind, in order to succeed a coin needs network effect which is created by the community willing to buy and hodl - tech is not sufficient enough (we saw this from btc's first generation shitcoin alternatives).
So far Monero has a community that is willing to buy and hodl, and if the community keeps buying and holding, more people will join into the party and that will accelerate the network effect and price surge to the Moon
TM.
If success = price being really high then sure your model works.
Personally it may be fairer to say that price play a part of success. To me it shouldn't play a large part of the "success" definition.
Success doesn't only mean people willing to buy and hold a crypto. Usage/utility and transactional/speculative
volume needs to be a factor.
If people are just buying and holding then it is essentially an example of the greater fool theory. Granted that is such a broad spectrum of things that is described as markets go up and down, but I personally would like it if people bought XMR if they need to, not want to just because of hoping the price goes higher.
Then again speculators gonna spec...cu....late.
Success may also involve a threshold of users/nodes that a crypto surpasses. Hitting critical mass is on the road to success, but is it success? I don't think so.
If it holds its adoption over long periods of time then yes it would be successful. But this is 2.5 years into the coin's life, kind of early to call monero successful...yet.