No, that information is not accurate. Operating a micro-powered AM or FM transmitter under Part 15 of the FCC rules does not typically require an experimental license.
FAQ Tag: part 15
Do Part 15 broadcasters receive call signs from the FCC, and if so, how can I obtain one for my Part 15 broadcasting operation?
Part 15 broadcasters, which include low-power unlicensed devices like Wi-Fi routers and cordless phones, do not receive individual call signs from the FCC. Call signs are typically issued to licensed radio stations, including full-power AM and FM radio stations, as well as television stations.