Up until 10ish years ago, the most popular SQL DB didn't support transactions in the default setup. So lots of apps got written without relying on having transa

Up until 10ish years ago, the most popular SQL DB didn't support transactions in the default setup. So lots of apps got written without relying on having transactions, either for compatibility reasons or because the devs grew up on said nontransactional DB. So autocommit was an easy way to emulate transactionless SQL on the rest of the DBs.