Even if the plane's filtration is good, if the person 3 feet away from you is coughing it's not going to be that good. I'd rather rely on the combination of filtration & a mask. Defense in depth.

Day to day i'm not religious about masking, but for things like public transportation, airplanes, etc I try to always have face protection on.

Pressurized airplanes have air changes per hour in the 12-16 range. That's above the ASHRAE recommended 6-12 air changes per hour for places that may contain viruses. (Obviously, ASHRAE isn't the CDC or healthcare organization directly, but they do know a few things about standards setting for HVAC.) Excellent filtration isn't as relevant when the average air molecule is in the aircraft for only 5-10 minutes.

The standard for AC/H for offices is 3-4.

The studied COVID outbreaks on planes show that this still isn't sufficient. I'm also pretty sure I got sick from the kid sitting directly behind me on the plane when I got influenza.

You can site all the statistics and propaganda in the world about plane ventilation. It clearly isn't enough to prevent viral spread (I don't care about air changes per hour or cfm or anything else, the only endpoint worth discussing is viral spread--I give precisely zero fucks about how fast the air is moving around). I'm using n95s on planes from here on out.

The real hazard is when you're on the ground. I've seen cabin C02 levels above 3000ppm when the cabin air handling hasn't been turned on!

I'll take my mask off to eat/drink in the air, which I didn't do the one time I had to fly mid-pandemic.

anecdotally, this is marketing bs / wishful thinking.

I've been on a handful of flights in the last 2 years where the air system didn't work at all, and others where the climate control system was otherwise failing (80°F). This is accentuated by stale air when you embark and disembark when the aux generators aren't providing power.

How old were the planes that this happened on? There has definitely been a dramatic improvement over the years. I remember flying in the 90's and pretty uniformly feeling like I needed at least a good face wash, if not a shower after any flight longer than a half hour. Now this only happens when I am unlucky enough to get stuck on an old aircraft (i.e. the original westjet 737's still get me with this). I swear I saw a paper on this being tested showing particle diffusion on some newer crafter being really impressive for how it kept your particles around you until they were removed and replaced with fresh ones fairly quickly but I can't remember enough to find a link to the study to back this statement up.

These flights were in the last 2 years on a top tier (US though) carrier on domestic flights; 1 was a very regional flight, where , as you post, an older plane might expect it -- but if anything, that any planes in a top tier carrier that markets itself as Covid ready are expected to be bad is typical of how much bs this is.