I do not believe that your problems are typical for FreeBSD servers.

I have been using FreeBSD servers for around 30 years. Most of them had Intel NICs and I have used at least 5 or 6 different kinds of Supermicro motherboards, both with Xeon and with Epyc.

Most servers have worked 24/7, without being rebooted for years and without having any minute of downtime except when I did some hardware upgrade or kernel upgrade.

I do not doubt that you had the problems described, but there must be some very unusual circumstances that have caused this. I would not be surprised if there was some problem with the version of Supermicro BIOS of your motherboards, and not with FreeBSD, because I have seen many bugs in Supermicro firmware. Or perhaps you had some buggy version of Intel NICs.

There is one advantage of Linux over FreeBSD, which is not widely known. Linux has a huge database of known bugs in various peripheral devices, including Ethernet NICs, and when one of those is recognized it applies workarounds for the bugs.

Like any other operating system, FreeBSD also implements workarounds for peripheral interfaces with known bugs, but because it has a much smaller user base also its database of bugs includes much fewer bugs, typically only those that had been reported by FreeBSD users. Because of this, I have seen cases when some hardware devices did not work well in FreeBSD, while they worked well in Linux, and the reason was always because Linux knew that they must not be used in the standard way, but it applied the corresponding workaround for their bugs.

Only Windows is shielded from the problems caused by bugs, because the hardware vendors write themselves the Windows device drivers and include in them any required workarounds for their bugs.