Not sure if it worked that way every where, tbh. When I say "less emergency surgery" I meant things like elective hip replacements, total knee replacements, cosmetic removals of benign tumours (my mum's had one on her shoulder for the last year and half that she is still waiting to have taken off because of the back log). I know my trust was very, very strong on keeping surgeries that would have life altering outcomes still going - to the point where we had wards that hadn't been opened for years re-opened just to house people recovering from said surgeries.
The trouble with it all is that there are - as you say - a finite number of resources. Theatre recoveries weren't operational because the staff were redeployed to ITU or the area was changed to an ITU. The vents that they needed for during operations were being used in ITUs. Anaesthetists and theatre nurses etc. were drafted to manage ventilated patients which created a massive hole in the system. That was half the reason lockdown was imposed - it wasn't because the NHS couldn't cope with everyone getting COVID, it was that the NHS couldn't cope with the 'normal' emergency admissions who needed a bed, oxygen and possibly a vent as well as the people getting COVID. Oxygen supply was limited because of a higher number of people needing oxygen (even people not on a ventilator, just people on nasal specs).
It's unfortunately not a simple thing that could have been avoided, no matter what the news may say. Even if we were fully prepared, at the peak of the first wave there were hospitals that had absolutely no capacity and some that were so low on resources it was down to senior staff to choose whether to turn everyone's oxygen down by a litre to conserve it further. You can have all the resources in the world but it takes time, training and expertise to be able to manage even one patient - there's no way really you can prepare a health service for that level of emergency or the speed in which it came to us IMO.