Why is spectrum not allowing recent phone models?

I have a Galaxy A54 that is currently on Verizon and would like to switch to Spectrum. In speaking with the chat agent, I was told that Spectrum does not support the phone on its network. In questioning this (since Spectrum uses Verizon), the agent eventually said that technically Spectrum could support the phone, but its a policy not to allow the phone. This came up because I considered switching a year ago and at the time I was allowed to switch, so I asked what would had happened if I had switched a year ago, would I now be kicked off - and the agent said I wouldn't be kicked off (which is good to know). Why is Spectrum not allowing a phone model that came out recently (March 2023) on the network? I'm bothered by this as I was told I should buy a new phone and that I should buy from the Spectrum store to ensure compatibility. That's a bit disturbing as the Spectrum store is very short on options and does not have lower price phones (this is for a person that does not need a newer model). Verizon had a huge selection of phones, including refurbished phones, so I could buy based on the need of the person in my family. While I'm bothered by this lack of choices, I would really like to see if there is a way to transfer my Galaxy A54 over so I don't have to spend $500+ on a new phone through the Spectrum store.