Transactional purchases is still an important feature of cryptocurrencies. It is often overlooked as new exciting features are developed or proposed. Also, early merchant adoption of Bitcoin ran into problems as Bitcoin was not ready (low percentage of users among customer base, difficulties with Point of Sale tech, clerks who lacked knowledge, slow confirmation times, not solving a real problem, and price volatility). Mainstream merchant adoption (especially brick and mortar) will come after many other improvements, broader adoption, less volatility, and second layers like Lightning.
The number and adoption of stablecoins has increased because it allows payments without the volatility concerns of other cryptocurrencies. Not all stablecoins are alike, and some will likely thrive while others fail. Tether has dropped below 90 cents on more than one occasion, violating the stability as well as causing further concern about a future collapse.