Contact in rugby starts at U9's, but it is literally just tackling and nothing else (rucks, mauls, scrums and lineouts), which get gradually introduced over the next few years. But yeah you do typically lose kids from that year onwards...and then girls and boys separate out from U13 upwards too.
I know the RFU has been trying to do loads around concussion with grassroots clubs in particular around recognising the signs and return to play protocols if diagnosed by medical professional. More needs to be done and particularly between schools, parents and clubs as all three have an important role to play in keeping players safe Not all concussions happen on the pitch (little Johnny/Jenny will fall off their bike/get pushed off a wall at school you know!)...and secondary concussion (ie sustaining a subsequent head injury) can and has been fatal.
I think grassroots rugby has been hit harder than football during the pandemic as there have been more restrictions on what they can/could do (football fixtures continued when rugby couldn't even train, for example).