Monero is a currency that distinguishes itself from the competition by one main characteristic: Anonymity. Offering opacity and security at each end of the transaction, it targets a very specific market. This added value can however be criticized in terms of ethics. When it comes to transaction anonymization, Monero is the perfect choice for any individual looking to protect their privacy. Although there is a panoply of anonymous currencies in the market, XMR remains the safest because Chainalysis has managed to crack the confidentiality code of some of them.
Monero represents a growing threat to the adoption of cryptocurrencies in general because I find it hard to see a regulator authorizing a currency that it cannot trace. If regulators could stop bitcoin, they would have. It's because they can't stop the Bitcoin machine that they are all forced to regulate it. Nothing obliges them to authorize anonymous currencies, especially as this one is more used on the Darkweb and can easily be used for criminal purposes.
Monero does not have long term viability, the closer we get to the adoption of cryptos, to regulation, the more Monero will be illegal with governments. Remember that Monero won its bet, that of being the leader in anonymous crypto.