It would have to alter the voice of anyone on it to make them sound ridiculous.
For yanks: https://en.wikipedia.org/wiki/1988%E2%80%931994_British_broa...
You omitted to mention that the Irish state broadcaster, RTE, actually implemented voice restrictions before the UK did:
https://www.rte.ie/brainstorm/2024/0119/1217560-section-31-b...