You can't connect the IP feed to most of the high quality audio reproducing systems.
How are you going to run it - on your smartphone with its mediocre speakers?
How about your mobile internet coverage? Do you have it everywhere or in select city centres?
a couple of other points
at home,
for 320 IP bbc stream I use a laptop, sometimes with external dac, but, more frequently the DVB(tv aerial) radio streams, on a humax TV box;
for home, DVB, represents a solution in the UK, as opposed to dab+
Since many folks have broadband at home, an IP stream radio, or DVB should be cheaper than Dab+.
I agree, that many people with BT headphones on a smartphone will be downgrading a decent feed to the std 128Kb/s BT codec, resampled on the Android mixer too,
so probably no better than 70Kb/s dab+ aac.
I am not sure an IP feed makes efficient use of the communication infrastructure, in so much it's not an optimised multi-cast communication afaik.
Mobile IP is more tricky, I don't get reliable 2G phone where I live, and don't use mobile 4G data in a car/smartphone,
but would consider switching to that if FM (whose reception is fine) was turned off, and a low bitrate DAB stream replaced it.
In the Swiss case, I don't know if they have a much higher transmitter density that the UK to support their DAB roll-out,
prior to the huawei debacle, I thought, 5years out, we would have a 5G station on many lamposts, to give massive mobile network coverage/bandwidth.