The hassle with autotuning digital TVs

For years with analogue TVs you just tuned in the channels yourself. Every decade or so a new channel appeared and you had to tune another button.

Then TVs got smarter and would find the channels for you. But (crucially) they let you delete channels and change the order of the channels.

Then digital TV comes along (Freeview), and says "sit back, I'll do it all for you". And then proceeds to get it wrong...

Where I live, I get a solid signal from Crystal Palace (London), and a poor signal from Bluebell Hill (Kent). So I want to take the Crystal Palace signal - I used to use Bluebell Hill solely to receive the analogue Meridian ITV in addition to the London franchise.
So, one sets an autotuning TV off scanning for digital signals. They all seem to scan from low to high, so what I'd like like to see is:

However, what I actually see is: i.e. it finds the signal on RF channel 27 from Bluebell Hill, which gives the TV channels on Mux A, and then finds another set of Mux A channels on RF channel 32 from Crystal Palace. The signal on channel 27 is poor, and so the picture breaks up. I need to take Mux A from Crystal Palace, even though it's found after the signal from Bluebell Hill. Most of the signals from Bluebell Hill are much higher in frequency, just that they use channels 24 and 27 as well (although I never seem to receive channel 24).

Now every set I've come across lets you manually scan channels. But how they handle the above problem varies. Some assume that you know what you're doing, and if you manually scan channel 32 then it uses the TV channels it finds there instead of the ones from the autotune.
Other sets use what you've manually found until you power the set off, and then revert to the autotuned ones.
Other sets stubbornly refuse to update their TV channel list at all. On these you have to do a full reset, and then abort the autotune. Then it reports no channels found and you can manually tune all 6 RF channels to get it setup properly. This is just hassle!

So, why can't I blacklist RF channels from the autotune, or delete TV channels from the autotune-generated list ?