I tend to hang on to clothes way too long so as my sizes have gone down from XXXL to XXL to XL over the past 6 months until recently, I could find things to wear. However, I am now wearing L shirts and I haven't been this size since college, so I have had to go out and buy a whole new wardrobe. The good thing with the pandemic lockdown is that I can wear sweats every day and only clothes to work out in and maybe a few pairs of jeans to go out in public with. I'm not buying expensive stuff though- Walmart and Costco are fine for now. I'll save the more expensive things for later when my size is stabilized.
To answer your earlier question- I have kept a few of my fat clothes, gotten rid of a bunch of them, and will probably throw the rest out after I have proven that I can keep the weight off. Maybe I'll do another purge of the closet this weekend. It feels good to move past that long chapter in my life.