Yes, the government would never accept everyone in a country on using an untraceable currency, but what if the people started to constantly asking for it?
People constantly ask not to go bankrupt from healthcare bills or for a wage they can actually live on. The government don't care.
Didn't Bitcoin survive the same way? Most of the governments were justifiably against a so anarchic currency from the very beginning. Weren't we reading FUDs that they'll turn it down, ban it, make it illegal? And here we are, eleven years later and it seems like it's succeeding more than ever. Why? Obviously, the people want it.
Some governments have banned bitcoin, and most of the ones which haven't are trying to regulate it to oblivion. The same and worse is happening to Monero, for example the IRS offering a bounty of $1.25 million (initially $625,000, but they doubled it when no one could claim it) to anyone who can track and de-anonymize Monero transactions.
Look, if the whole world decided to adopt Bitcoin and Monero as global currencies, I couldn't be happier, and I will continue to use both in the most private possible ways. But I am not naive enough to think governments like those of the US or China are going to let their citizens use a currency which they absolutely cannot trace. The need for privacy is only going to grow over time, as is the government's desire to invade it.