Restrict block in Layout Builder Browser by new Block bundler permissions

I created a fork which adds a check to ensure that the user can create the inline_block.

I created a fork so that the new block create permissions are respected by layout builder browser

I think you are confusing non-inline block_content entities with inline block_content entities.

The "create block content" permission reflects to creating block contents which are NOT inline
e.g. on https://yoursite.com/block/add/image

This permission does not target inline blocks (You can test this by disabling layout builder browser, the inline blocks are still available even without above permissions)