We know that SwSh will have around a 1000 total Pokemon, including different forms. Doesnt a 1000 mean that there cant be that many Pokemon cut?

We also know Megas are out. What keeps being repeated is that the pokemon staying are based on what fits in the Gallar region and story. This means that region-specific legends are likely to be out. Ultra-beasts are out nearly 100% certainly.

These together leave space for the new generation being introduced but you still need most of the older generations to even make it close to a 1000.

Call me out if I'm being crazy or retarded but given this news and these numbers, I dont think its possible we'll be losing all that many mons.