since taking down a coin's anonymity with masternodes like Dash is far more easier than taking down a coin that doesn't use masternodes like Monero.. Thats it. If a scenario came where the government was banning all use of cryptocurrencies etc, you can expect masternodes on coins to be one of the first things taken down by the government.
OK so Monero lives on longer than DASH in the face of Guv/TLA, is that your point?
Aside from this Guv scenario, as I said, the real-world fit-for-purose debate is surely around lesser adversaries. In this case DASH is fit-for-purpose IMO. On with adoption!

The challenge of finding the nodes? The ip's of all masternodes are in the open.
OK fair comment.....is it possible to obtain monero node IPs?