Owner doc wants to add an associate

I’m a newer dentist working my first gig at an office with 4 dentists. All associates including myself produce around 100k a month. I have an upward trend since I’ve only been working a couple years. Owner doc wants to add another associate but the associates and I are arguing against it. Obviously it’s his business so he can do whatever he wants. I feel we are operating under max capacity. The whole office works hard to keep things running— no one wants the stress of another doc. We are frequently running into situations where we wish there was another operatory. I have no idea how this would work. I think this has the potential to ruin a good thing. All the current docs would produce less because of a new doc. Am I missing something? There is no way this could be good for anyone other than the owner doc right?

Someday I want to open my own place or be an owner but I don’t have any savings for a downpayment and credit score isn’t good due to some bad choices when I was younger.