Need a review on my upload

The issue I explain below is not one I could get assistance with via the normal chat route. So far I've only gotten back generic "everything looks good" or circular support. I'm hoping that in this attempt I've been able to give a clear explanation of the problem so that I can get the support I need. Thank you!

The Problem

I'm capped at 45Mbps upload across all forms of connections; wireless and wired (into router). From what I understand, I should be able to get up to 300Mbps at my location. As you'll see below in my speedtest results, I am not having an issue with download it's all upload. Since I've been in this location (4 years, I believe) it has never exceeded ~45Mbps. Also this isn't a consistency problem or an intermittent one, no matter the time of day I will always be capped at ~45Mbps.

My Hardware

Modem: NETGEAR Nighthawk Multi-Gig Cable Modem (CM2000) (tech specs)

Router: ASUS ROG Rapture GT-BE98 PRO (tech specs)

SpeedTest Results

Wired

Wireless

What I'm Looking For

Some help would be greatly appreciated! I'd like to understand why I can't exceed ~45Mbps. Yes, my internet is working, and I'm not even asking for 1:1, I just really need it to be closer to the expected speed of 300Mbps and from the years I've had Xfinity my speedtests all seem to point towards an intentional ceiling on my upload.