Yeah, the physics for damaging zombies was altered to have less depth. Limb damage and gradual dismemberment are now gone. Head explosions are present, but will only happen with critical hits, which were also altered. Handgun-type weapons have a higher chance of scoring a decapitation than shotguns, despite that making zero sense. It's possible to get zero head explosions with a shotgun in an entire playthrough.
Talking about zombie physics reminded me of the hospital siege with Carlos. The RE Engine couldn't handle that many persistent corpses in a single area, so the developers altered the death animations, making zombies disappear in tiny red explosions accompanied by 'sploorch' sound effects. Super weird and immersion breaking. It also made me question why the devs would even include a zombie siege if they knew it didn't play to their engine's strengths.