See and be seen is a requirement of flight in VMC - that's true regardless of whether you're VFR or IFR, and regardless of the type of airspace you're in.
The only time that this becomes difficult (ok then - it's always difficult, but it becomes even more difficult) is when one aircraft is flying in a cloud, and another is flying outside the cloud, but very close to it, such that there is only a very short time between the first aircraft exiting the cloud and the two aircraft coliding. This is why a reasonable vertical separation from clouds is required when flying under VFR (with an exemption to allow VFR flight underneath low clouds).
Personally, I wouldn't like to be flying near to, or in, clouds without using some kind of radar service if it's available. Doesn't matter what type of aircraft I'm in, or whether it has an engine or not. But that's just me. And anyway, it's a big sky, and sometimes radar service isn't available.
FFF
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