Look closely at Step 2 photo. The friction material is missing on one brake shoe and lifting on the other. If the disc/drum is hard to remove, it is likely there is a lip on the drum edge that is catching on the brake shoes. Bashing the disc off will likely damage the friction material on the shoes. It would be better to back off the shoes by turning the star adjuster with a flat blade screw driver poked through the wheel bolt hole. Just remember to adjust tight enough so the wheel locks, then back off a couple of clicks, after putting on the new disc/drum.

Love the explanation how to take the disc off, tap it off, and then you show a picture (step 2) of a parking brake shoe minus its friction material. If there is a lot of resistance, the possibility is a lip has formed on the drum part, so backing off the adjuster for the parking brake is needed to remove the rear disc/drum. Otherwise get ready to buy a couple of new parking brake shoes (so as not to be a parking “break”).