Correct me if I'm wrong, but in the UK you can make an unlimited gain on stocks and shares tax free in an ISA. The only restriction is the amount you can place in it per person, per year (£20k) and the vast majority of people aren't going to be putting that into savings in a given year.

If the rent is less than the opportunity cost of your deposit along with mortgage payments/maintenance taking into account possible gains in the house value as opposed to the stock market then it's plausible you could gain tax free assets faster via investing in an ISA than property ownership especially taking into account the extra opportunities you may be able to take advantage of by being able to move easier for a better job.

I personally am a home owner because I value having control over my environment (decorating, pets etc.) although that could conceivably be fixed via legislation as others have alluded to.

I'm not sold that avoiding home ownership is the best way to accumulate capital in the UK, but I don't think it's completely out of the question as you seem to imply.