I don’t know if I understand you correctly, but it’s actually very possible to go back to the previous app with just one swipe. No need to return to home screen. I have iPhone 11 Pro (should work the same for any newer models too) and you just swipe at the bottom from left to right and it will switch to the previous app you had open. You can do the same gesture from right to left to go forward to the next app. You can continue the same to shift through all your recently opened apps.