Working for Toyota is not bad at all... but working for a BAD Toyota dealership IS.
The dealership that I worked at didn't like to suggest the right repairs, and also ignored a lot of problems on certain vehicles... which made my job as a technician really aggravating.
Find a GOOD dealership, and working as a technician is very rewarding, but if you are stuck working at a dealership that doesn't do things properly, then you will find yourself annoyed with your job.