Top 10% of household income with some savings for a downpayment should indeed be able to purchase housing if they choose to tie themself down that way.
It’s not necessarily the case that top 10% individual income means you’re top 10% household income (and the top 10% household income can obviously bid more for housing than the second, third, or farther decile of household income).
A household (not individual) income of £100000 is sufficient to be well inside the top 10% by income. Using the standard ratio of 4.5 times income for a mortgage means that you are capped at houses costing around 560k, assuming you have 20% to put down.
The following search for 3 bedroom houses [1] provides either flats, maisonettes and a few houses in areas with poor transport links, and many of these are still over budget.
Nothing is wrong with purpose-built flats or maisonettes - I personally live in a high rise! Most people I know looking for a place to live with a family etc are looking for a house though.
It’s not necessarily the case that top 10% individual income means you’re top 10% household income (and the top 10% household income can obviously bid more for housing than the second, third, or farther decile of household income).