Yes and no.

Yes because our bodies need some exposure to these organisms to build immunity.

No because u cannot compare with yr dad's younger days because the organisms have mutated/evolved to stonger and deadlier stuff so u have to take precaution to that. The drains that yr dad played b4 are even more dirtier now...do go to the drain n c if u wanna play in it...our factories are producing much more waste then before as well as deadly added chemicals never seen before back 20 years ago...