Historically, the market was regulated to prevent new entrants from entering the market and preventing competition. In NYC, this was a hard limit on the number of taxis with every taxi requiring a medallion. In suburban towns, taxi companies typically need to be licensed by the town and some towns have limited the number of companies or total taxis.

Uber really disrupted that as it rolled out across the US and other countries by basically rolling out illegally and then getting customer support to change laws.