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I have. Quoting myself:

While references to living saints are numerous, they are never a substitute for “all Christians” or “everyone in your church”: St. Paul makes a reference to a group of people perhaps visibly designated or perhaps not, but always a select group in his mind. The “saints” to Paul are subject of imitation: “receive her in the Lord as becometh saints”, he urges in Romans 16:2. It appears that these “saints” had an ability to judge, not only judge the world in the afterlife but also adjudicate daily disputes:
Dare any of you, having a matter against another, go to be judged before the unjust, and not before the saints? Know you not that the saints shall judge this world? And if the world shall be judged by you, are you unworthy to judge the smallest matters? (1 Corinthinas 6:1-2)

Observe a curious turn of the thought: some Corinthians apparently had gone to a non-Christian judge whereas St. Paul expects them to resolve the dispute “before the saints”, but in the next statement he puts the transgressors themselves as putative judges: “are you unworthy to judge”, he asks. This discourse reveals an ecclesial court of peers where select parishioners are asked to judge other parishioners. It is then those capable of judgment that St. Pall calls “saints”...
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Pauline “saints” are a select group among the parishioners in the church.
This distinction is even more apparent in these passages:
concerning the collections that are made for the saints… (1 Corinthians 16:1)
concerning the ministry that is done towards the saints… (2 Corinthians 9:1, and several similar)

So the saints to Paul are not the entire local church, but a select group that is a beneficiary of a special ministry; donations are gathered for them from among the parishioners. We don’t know much further; perhaps these “saints” were the elderly in the church, perhaps they were distinguished by their special dedication to the church. They could be some early form of nuns and monks perhaps: people who renounced their possessions and literally lived in the church.
Clearly, not every believer was a saint according to Paul.
on some other occasions St. Paul speaks of sainthood as an aspiration:

to them that are sanctified in Christ Jesus, called to be saints, with all that invoke the name of our Lord Jesus Christ (1 Corinthians 1:2)
the beloved of God, called to be saints (Romans 1:7)
to them that love God, all things work together unto good, to such as, according to his purpose, are called to be saints. (Romans 8:28)

In all these quotes, unlike the two previous groups, the reference is explicitly made to all Christians, that is all who believe in Christ and love God, or receive God’s love. But to Paul they are not quite “saints” but rather “called to be saints”. That then matches the modern understanding perfectly, where we think of all believers as being on the road to sainthood, rather than necessarily sainted already.

In short, the idea that every baptized person is a "saint" accordingh to how St. Paul used the word is another Protestant hoax.