It is a fact that global equities, and in particular US equities have out performed U.K. equities by some margin.
And I don’t know where you get your 40% equities on PF from…most default funds in the core investing periods are around 60% equities. And are in gobal equities. I think the overall average is less than 10% invested in the U.K. I am at 2.5%. Many self select a higher equity % - I have been 80% in equities, underweight in U.K., for the best part of 20 years and done very well as a result.
Old fashioned thinking was that as you neared retirement you switched from equities to bonds, and perhaps that’s where your 40% comes from. But, as an investment strategy for a drawdown pension over what in my case could be 40 years that’s fatally flawed - the drawdown period will be longer than the investing period so I intend to continue to be heavily equities weighted for at least the next 2 decades to benefit from long term growth. And I don’t see that coming from the U.K.
As for foreign investment in UK infrastructure that’s usually for the income / dividend stream, providing predictable cashflow. Quasi bonds you like, with a higher return than government bonds. And income should form part of anyone’s investment strategy. But being overweight in that type investment will hold back your overall investment growth and therefore long term income potential.