Shareware CD-ROMs, either real or as ISO, are/were a good source of shareware, freeware and public domain.
They're also anti-virus checked and read-only.
Downloading them shouldn't be an issue, either.
Because, the shareware rule (license terms) of the 90s said that a copy is not allowed to cost more than the medium is worth (plus a little compensation for the work/shipping).
Or alternatively, below a maximum price - it was $5 or $10 or something along these lines.
So strictly speaking, many larger compilations were violating the rules themselves, back in the day.
That's not to be underestimated, I think, because some of the included readme files of the shareware products confirmed that.
And they were applicable license documents, like GPL v2, perhaps.
PS: Speaking under correction, of course. I'm no lawyer, either. I don't take any responsibility for the statements made, thus. It simply resembles my understanding on the matter, be it right or wrong.
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In what to one race is no time at all, another race can rise and fall..." - The Minstrel
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