I suggest You to buy another PS3 console or continue to use your PS3 like you have done until today.
Be banned is a risk that everyone that use the console for his own purpose out of the standard of the owner company know well so.. if you like online game don't jailbreak your console , this my advice .
you are right, but... it's too late
by the way, it is not so easy to know exactly what someone do on a console or a pc: if I delete more tracks as I can, I should be safe... I don't think Sony has an automatic system to recognise jailbroken consoles and - at the moment - no one has been banned because of jailbreak... on the web, lots of people just like to create panic, even with fake images of ban.
I'm asking all these questions just because I'd like to be sure that I will not be banned, and even because if I find a valid method to avoid ban, people could jailbreak their consoles without losing online play