The two largest co-morbidities are pneumonia and respiratory failure (each a larger number than obesity in all age groups, according to the CDC data). Other significant co-morbidities are heart failure/cardiac arrest, sepsis and kidney failure. The last one of those people can live with I guess, but the others are probably to a large degree caused by the viral infection. Also, it's not like most people with obesity or diabetes were liable to suddenly worsen and die unexpectedly, without covid-19.

Sure, 80% of infected people can manage at home, but that still leaves a significant fraction who need to be hospitalized. Hence why hospitals are being overrun in large parts of the US (and the rest of the world, for that matter). And that is with me of the strictest restrictions in peace time. One estimate I saw put the number of deaths prevented by lockdowns and other measures at 3 million deaths until June, only in the EU.

The US currently has over 100 000 people hospitalized with covid-19, 20 000 of those in ICUs. (In late September, those numbers were 40 000 and 6000, respectively.) And this is in a country with around 900 000 hospital beds, of which about 100 000 are ICU beds. So that means that about 15% of ICU beds and 10% of all hospital beds are currently going to covid patients, since the number of ICU beds has probably been scaled up when needs have increased.

Also, the high estimates for a really bad flu season is 90 000 deaths, a more typical number is 40-50 000.. This is at 300 000 now, in just over 9 months and 2-3000 new every day. So quite probably 400 -500 000 in a year, unless it suddenly drops off. That's 10 times worse than the flu, with all the restrictions put in place.

Sources: Covid hospitalization http://ourworldindata.org/covid-hospitalizations
Co-morbidities http://www.cdc.gov/nchs/nvss/vsrr/covid_weekly/index.htm
Hospital beds http://www.aha.org/statistics/fast-facts-us-hospitals