Privacy is a necessary feature in my opinion, but why hasn't Monero become a main coin?
Maybe Due to lack of demand and market correction it has not yet recovered, but if those who already understand what Monero is, they will happily continue collecting and accumulating to this day.
Anyone would rather than avoid to use this privacy coin instead of being accused by government to do criminal activities and being jailed. Privacy is not a major concern for anyone in crypto. To be transparent, they agree to provide their identities to the exchange site.
Privacy coin may not be needed again. The regulators can easily accuse people who used privacy coin to be connected with some criminal activities. Monero is good only for p2p transaction.
The beauty of privacy coin already burned by regulators with so many restrictions.
That's right, apart from that, many have adopted a model like the Monero coin developed and it may be more comfortable and safe from the eyes of regulators and other institutions who continue to look for strange issues related to things that are not good in digital transactions.