As we all know, it's common to see folk on bikes on the roads after dark who inevitably wear dark clothing and have no lights on said bikes. This is something I'd be too scared to do in case of the inevitable. If as a driver, you had a collision with said cycle user, you can bet your bottom dollar they'd try and blame you for the event.
Or is it just me being too cautious - ?
Not sure it's cautious but it's too something...
Firstly, I wouldn't ride unlit because I like to see where I'm going and don't like being delayed being stopped by the police and fined but it's not a major factor in collisions - only about 2%. That may be because unlit riders assume they've not been seen and give way more, or because street lights are so bright now that the minimum 4 candela bike lights are basically irrelevant.
Secondly, they can try to blame you whatever you wear, but it doesn't make it right. Wear dark colours and they can say you didn't obey the highway code. Wear green, yellow or orange and they can say you were low contrast against the sun or other lights or concrete/brick/hedge/crop colours. Wear pink and you'll blend into the roses and tulips grown in Norfolk. There's research suggesting that what matters is contrast not colour and the best choice for contrast varies too much to say one should always wear any particular colour.
And then there's the basic problem that once they've hit you, you've pretty much lost already - even if they can't blame you, you're still far more likely to be hurt than them.
And then there's the problem that "be seen" advice is BS. There is nothing you can do to make other people see you - and if there was, you'd only be distracting motorists from other road users and putting them at risk. Generally, we must push back against that victim-blaming and put the emphasis back on the approaching road user to look and only drive so they can stop within what they can see to be clear.
In short, you can't win by pandering to bad motorists and fear of what they may say if they screw up. So I prefer to do what I think best, which is to wear whatever I like and look reasonably normal/human (which usually seems to mean dark colours for me - avoid looking like an invisible gorilla or Somebody Else's Problem Field or a piece of street funiture which invites them to treat me as an obstacle instead of a person) and to spend the money instead on good German-spec lights for night. Frankly, if they can't see a fairly large adult on a rather large bike, or my lights at night, their eyesight problem is not going to be fixed by my clothing, no matter what evidence-free shoot is in the highway code or put out by the failed, bigoted "road safety" lobby.
They also shouldn't be able to prove that my clothing made them hit me, so it shouldn't even reduce damages if I stick to my guns.
So no, I'm not worried and I've had a lot less shoot off motorists since I stopped dressing as an alien space lemon and started dressing as an ordinary human again.