TWC legacy to Spectrum shift - Time Warner Internet

This question is about "TWC legacy to Spectrum shift", with Time Warner Cable internet and apps. Hello!

New member here trying to understand the whole TWC legacy mumbo jumbo. So, I called the customer center to ask about migrating from TWC legacy package to Spectrum. I pay a lower rate on TWC legacy but was told that I'd have to pay a higher rate to transfer to spectrum because spectrum bought TWC. There is no difference in speed or upgrade options.

I was told that Spectrum will offer Modem+ router combo for an additional rental fee but I have my own device now.

Is it necessary to migrate from TWC legacy to Spectrum?

Is it necessary to rent a spectrum modem/router for a higher rate?

How does Spectrum compare to ATT or Google Fiber in OC, CA?

TWC legacy to Spectrum shift?