I think the ask is for something like let a bit flip inside the UDP packet or let a byte fall out of the UDP packet. The integrity of UDP packets is still checked for (at different layers).
For most networks the error rate is so low that I don't think it's that valuable. Also you'd still want your metadata checked otherwise it'll get potentially delivered to the wrong place.
That's what I assumed they meant but there's so many layers of correction/protection going on and most of it is non-optional if you want a working system. For example, if you disabled the FEC that's used over high-speed serdes links within a core router you'll be left with a broken system, the error rate is much too high. In the designs I've worked on you can't disable the internal CRC/ECC on the databuses without risking corrupting the control data, which won't end well. Nobody provides separate data and control ECC protection, that's pointless overhead.
I guess they probably meant disable checking the ethernet FCS, that might still work but I think it's a very bad plan. I doubt this option is even exposed to network operators.
For most networks the error rate is so low that I don't think it's that valuable. Also you'd still want your metadata checked otherwise it'll get potentially delivered to the wrong place.