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I would say that there is clearly a performance advantage to making the engine have "interference" in the valve & piston stroke envelope. Namely that you can get more valve stroke or duration of being open and also that you can deign a better combustion chamber if you're not having to push the valve seats up high relative to the mating interface of the head. I also think that the valves at an angle may help in generating a better swirl in the combustion chamber. All of these things would aid combustion efficiency.

I have owned a number of old Mercedes six cylinders, and even though these have the valves square (in-line) with the pistons, they still are "interference engines". The intake valve chases the piston down closely on the intake stroke and the exhaust valve closes just ahead of the piston in the exhaust stroke. This has been this way for Mercedes even in the fifties. No one ever thought much about this on these because timing chain breakage is pretty rare.