A survey of cryptocurrencies showed monero has failed to achieve this goal of being a superior form of digital cash, relative to most other crypto currencies in similar 'weight class' of market cap and years available. This failure isn't technical, it's due to relative weaknesses in the realms of politics and soft social influence. Even the lower market cap LTC is more accepted as 'cash' by most legal vendors.
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re: below muh sources
getmonero.org, OPs referenced website, advertises cryptwerk as a good directory.
Go to https://cryptwerk.com/pay-with/xmr/ and compare it to https://cryptwerk.com/pay-with/ltc/.
There are ~twice as many for LTC for example, and that's being charitable with something with a lower market cap rather than BTC which is like 3+ times as many.