I could strip my bike down to next to nothing with just my multitool i take out on the trails. Add a 8mm and a 10mm spanner, flat screw driver and ill have my forks and brakes stripped down too.
Only bits that need special tools are cranks, bb and cassette. I like tools so i have the proper tools for those too. Although id be annoyed if i had tools that never got used just because things changed