It was. The cost of BBC radio is currently paid for by everyone with a TV licence. How should it be paid for under a subscription model when presumable far fewer people will be paying to watch BBC TV? Should the cost be borne by them alone? The alternative would be the taxpayer maybe, making BBC radio state controlled..
Apparently BBC radio has nothing to do with the license fee….
https://www.tvlicensing.co.uk/faqs/FAQ102
The TV licence is what funds the radio side though even if you don’t need one to listen