1. covid-related mortality and morbidity would not make up for any drop in other excess deaths
2. short-term stops on all non-critical care would, on balance, result in a significant drop in excess deaths over longer-term stops on a smaller percentage of non-critical care
3. hospital systems and their staff would still be intact after such a large wave. This may sound crazy, but while we're trading anecdotes you may be surprised at how many ICU nurses considered quitting because of how hard the latest surge hit. These are the people who dictate how many "ICU beds" we have, not the physical beds themselves!
4. that we can make any kind of meaningful analytical statement on covid mortality vs excess mortality for a specific age group given the lack of reporting data on both. In particular, data from coroner's offices on covid deaths has a huge lag time at present. Looking at case counts only is a poor proxy given you have to model infection -> death/recovery/discharge lag times, geographical variations and healthcare capacity as well. The HMD link merely provides total counts and proportions with no additional commentary. You can find more specific discussions on the subject [1], but they don't cover demographic breakdowns over time and necessarily maintain a high degree of uncertainty.
I don't think it's controversial to say governmental policy here has been sub-optimal at best. But to say that one extreme approach or the other is what we ought to have done based on woefully incomplete data is a stretch too.
[1] https://health-infobase.canada.ca/covid-19/epidemiological-s...