"Sufficient pectrum should have been freed up in anticipation and the question not arise"
From where? you can't just conjure up frequencies from nowhere!
This isn't really my area of expertise, it is the company I work for area's of expertise though...
one of the main reasons behind freeview was always to squeeze more channels into a smaller amount of bandwidth, therefore to free up a frequency range for other uses, it was always known that there would be a possibility the new allocation of the freed up frequencies could interfere with freeview, the level of that possible interference wasn't realised fully 20 years ago because nobody predicted the insatiable need for fast mobile internet the general public would have.
Now it's happening it's been realised that a small percentage of people might need to install a filter (which will be provided for free) and an even smaller amount of people will need a mast head filter, it's no big deal though, the amount of people it will effect is a minute percentage of the population, but of course this has been blown out of proportion by the media..
It's very easy for people to be armchair warriors, but if you can't suggest a better (and workable) way of doing anything then you are not in a position to criticise.