I’m aware of the danger of the “recency fallacy” that leads commentators on pronunciation to claim that a pronunciation is getting more common when it really isn’t.
But I do feel tempted to claim, though admittedly without proper evidence, that the strong form of Saint is becoming commoner, where I would expect the weak. I would never use the strong form in names of saints or in placenames based on them. For me St Matthew, St John, St Agatha, and likewise St Albans, St Helens, St Leonards-on-Sea all have sənt, or forms still further reduced such as sn̩t, sn̩. It’s sn̩ Thomas’s Hospital and sm̩ Paul’s Cathedral.
My impression is that people have recently (= in the last twenty years or so) started pronouncing these with the strong form seɪnt.
OK, I know Americans often do this. But I’m talking about Brits.
My late father used to like to recite a verse referring to pairs of apostles who share the same saint’s day in the calendar of the Anglican church (1 May and 28 October respectively, since you ask.)
Let us emulate the aims
of St Philip and St James
and be very very good
like St Simon and St Jude.
And all the Sts were reduced.
(His mispronunciation of good as ɡuːd instead of ɡʊd, to make it rhyme with Jude, was intentional.)
Do we blame the decline of religion, that we don’t talk about saints very much any more? Or do we attribute it to American influence?
Correction: we’re phoneticians. We don’t blame, we observe and seek a reason.