Expansive carrier boards for the Raspberry Pi Compute Module 4 certainly aren’t unheard of, but the $99 Interceptor Carrier Board from Axzez, with five SATA ports and four gigabit Ethernet sockets (as reported by CNX Software) certainly stands out.
The Interceptor carrier board is designed to be the center of your NAS. Those five SATA ports are connected via a JMicron JMB585 PCIe to SATA controller to a single 5Gbps PCIe interface, which may create a bottleneck, while the network ports connect to a Realtek RTL8367RB switch. This looks like a board custom-made for a home-made NAS or managed switch, and the only thing it lacks is USB 3 support, as both the Type-A ports built into the board, and the extra two nine-pin headers, are USB 2. Video is taken care of by a pair of full-size HDMI ports capable of 4K 60Hz output. Missing from the board is the ubiquitous 40 pin GPIO. While not strictly necessary for the intended market, it would've been nice to have some basic GPIO options.
A Raspberry Pi OS Bullseye image is available from the company’s website which contains all the necessary drivers, and there's a forum for asking questions on. Pre-orders are currently being taken for the board, which is being offered at $99, to ship in February.