Monero is not on all exchange and there are some exchanges that has removed the trading pair from there platform because of some many reasons we might not have idea about but all we can do right just to look for exchanges that one can trade it without issues.
Number question you need to ask yourself is why do you think monero would be seen as an alternative for fiat?
The government are still agitating on Bitcoin so why do you think monero is the best to compare with fiat.
Monero doesn't need to be on exchanges to survive. People can just trade Monero in-person (Face-to-Face), or through a DEX. When paper money becomes a thing of the past, XMR would be our only option for true financial freedom and privacy. I didn't include Bitcoin because it's NOT a private currency. Transactions are fully visible on-chain, and can be tracked by the authorities anytime. Just like a credit card.
XMR is comparable to paper money because you just send the payment without anyone else knowing the transaction amount involved (except you and the person you're dealing with). I sure hope we get enough time to enjoy paper money before the whole world gets dominated by CBDCs. Once these government-backed digital currencies rule the world, you can say goodbye to privacy for good (in Fiat, of course). Just my opinion
I understand your point, and the point for monero overall as crypto money was designed to be resilient against regulations, but when CEXes were forced to accept new regulations, and traders welcomed them as well, prices grew with them as people were trusting exchanges more. Now those regulations showed what they are really for, and all money low that came with regulations adoption and institutions, leaves from monero marketcap.
Monero might stay alive by people trading it p2p, but imho it never reaches ATH, as high liquidity that came from CEXes is gone. With liquidity and marketcap going down, people will think twice if they accept monero as a payment, because if less and less people accept it, because it's harder and harder to turn to cash, and we are not sure if someone will accept monero as a form of payment in the future, that doesn't really inspire investors confidence. Especially if btc works as a store of value for them as well.
I would like to welcome a future where private money like this would be relevant but i can't just see it. As anyone following FATF has seen where regulations are going for a long time, and to me monero has been a zombie coin and this kind of privacy, that's meant for evading regulations has pretty much lost the battle. There might be privacy via ZK but this has to be auditable to have some level of transparency that fits with curent AML laws.
So unless there will be a new kind of world order that welcomes corruption and opacity, no matter who is doing it, i believe that privacy coins will become next to impossible to trade, as because of no fiat ramp won't accept that as a source of income. And because of travel rule, you need to provide that info.
So i can't see any reason why people rather wouldn't accept cash or btc. Big amounts of physical cash might be hard to explain, and i wouldn't hold that, but at least that can be easily used for day to day purchases, unlike monero.