I do come across threads that have been inactive for more than four months and all of a sudden you will just see a user make a reply on such post that have been inactive for a long time and possibly the discussion is the OP looks concluded from previous replies of other users and this is mostly done by newbies so is it necessary to wake up an inactive thread
First you can see those inactive threads pumped by newbie accounts but it does not stop here.
Next is not newbie members, but high-ranking members, who did not notice how old that thread is, not only four months but maybe four years or older, was pumped by a newbie. They joined those discussions and did not know that they just replied to a non sense post from newbie.
I don't know how newbies can find threads that already are inactive some years, and bump it.
the OP is to be blamed for not locking the thread when the thread became inactive and the information required by the OP has been ascertained
OP can lock it and should do it but if OP did not lock it, months later, it was bumped by newbies, it's hard to say the spam is because of OP.
Other posters who join those discussions have responsibility too by did not read OP, but only reply to a newbie's post to reactive an inactive thread.