That's a valid point, yet if they're convinced to try the kit without the proper tools, materials and working environment for best use of same just invites failure on their first attempt, with impaired motivation to try again a second time when better prepared.....
Simple instructions free up people to at least try gun building, very complex instructions will definitely drive them away.
Jim Kibler, in his "how-to" videos on assembling his kits, is pretty emphatic on having the proper tools, materials and working environment. Saying a first-time builder can do it successfully with a pen knife in their lap does a disservice to providing reliable and useful advice for their success in their first project.