Why some files in /sys/devices/virtual/net/ return "Invalid argument"

Issue

Some tools like collectl (not supported) use data from /sys/devices/virtual/net and return "Invalid argument"

Example

# collectl
waiting for 1 second sample...
cat: /sys/devices/virtual/net/lo/speed: Invalid argument
cat: /sys/devices/virtual/net/bond0/speed: Invalid argument
cat: /sys/devices/virtual/net/bond1/speed: Invalid argument
#<--------CPU--------><----------Disks-----------><----------Network---------->
#cpu sys inter  ctxsw KBRead  Reads KBWrit Writes   KBIn  PktIn  KBOut  PktOut
   6   3  4879  11298      0      0     61     24      5     35      4      24
   0   0  3987   6623      0      0      5     10      4     31      2      18