"Let me know how long that passage or entry door holds up with modern lazy joinery vs. actual M&T."
Is 35 years long enough for you?
A well proportioned, fitted and glued spline tenon is quite sufficient for most purposes. In conjunction with cope and stick tooling it can be a good choice for doormaking. I have a hollow chisel mortiser for situations that call for square-ended through mortises or where the pieces are too small for inserted tenons like sash joinery. Otherwise I find myself using the stationary slot mortiser or Domino.