Good point about the possibility of the a/c being unrestrained and rolling forward whilst the crew's attentions is quite rightly focused inside on what the hell happened.
Further, I see so many times in the sim that, contrary to Boeing's ideal world, a significant number of pilots disarm the autobrakes with their feet in the stress of the RTO, thus rendering the SOP of not setting the parking brake because the RTO will keep the a/c safe as non- effective.