Why are blind mortise and tenons used when a dowel joint is quicker and easier to cut and possibly stronger?

To keep it simple, if we look at the one thirds rule for joining two pieces of 3" x 1 1/2", the tenon would be 2" x 1", giving a glue area of 6" x whatever depth. If 2 x 1" dowels are used (same depth/length) then the glue area will be 6.28" - theoretically stronger.

Am I missing something?

To keep it simple, if we look at the one thirds rule for joining two pieces of 3" x 1 1/2", the tenon would be 2" x 1", giving a glue area of 6" x whatever depth. If 2 x 1" dowels are used (same depth/length) then the glue area will be 6.28" - theoretically stronger.

Am I missing something?