It does seem to have got a lot more evident in recent years. Not really solving the underlying issues leading to there being so many in the first place, but some homeless do accept contactless donations[0] and there is a city-wide contactless donation scheme[1].

[0] https://www.standard.co.uk/news/uk/homeless-people-wearing-b...

[1] https://www.bbc.co.uk/news/uk-england-london-46372244 and https://www.taplondon.org