not true. if you make a repair, you're liable for it. if you do your job well, there's no reason that would mean more of a business risk than the OEM takes.
If, on the other hand, you do a rush job, then yes you're very much on the hook.
If anything, this makes repairs/reuse of devices more interesting to the consumer, since you know that some basic level of responsibility (read: liability) is taken care of.