That’s kinda what I am thinking too, it’s a big range of what’s “normal” My thoughts are that I lost a lot. 2019 I was running 10 mile road races and putting down 20-40 miles a week. 2020 I went out west hunting elk and averaged 18 miles a day in hiking with a 50 pound pack for 7 days at 10k feet.Unless you had a previous PFT before illness to compare to the current PFT you will not know how much had been lost.
The "within range" is only compared to what they think your range should be. Initially you may have been well above range and now down into a projected range. So there could still be significant loss.
today I can’t run 1/4 mile.
it’s anecdotal because I don’t have a prior PFT but I highly doubt I was on the low end of the range prior to covid.
I would highly suggest that anyone who hasn’t had covid or the vaccine go get a baseline PFT before you get the vaccine or covid.