Why would you use a PPO? The average SWE can be on an HMO. HMO's are fine. I have never once regretted choosing an HMO.

Additionally, you're using the average software engineer salary in the US but then picking California for rent. The article you linked says country wide you'd expect $1950 for renting a 1-bedroom not the $2500 number you are picking for a studio in the bay area.

So you're off by something like $1000 per month (edit: I admit I am simply looking at what I pay for HMO, it's possible that is somehow unrepresentative but I doubt it) by picking the most expensive health plan and mixing up national salaries vs very expensive areas.

The gun violence risk is vastly overblown. The page you are linking to cites a study where gun deaths are being accumulated for ages 1 to 24 years old. Gun deaths are highly non-random and concentrated in older ages and in very specific areas (largely related to gang activity). The average software engineer with family is not going to run into any of that unless they are in the habit of leaving loaded weapons around the house.