Suppose someone obtains a PPL-ASEL, then obtains a type rating in an aircraft requiring that rating e.g. jet, etc. This type rating functions as an instrument rating, allowing the pilot to fly the new aircraft under IFR. But does said type rating then grant the pilot the privelages to operate ANY appropriately equipped airplane single engine land under IFR as well?
61.63(d)(1) requires that if you don't have an ATP that you hold an instrument rating to obtain a type rating. The type rating itself does not grant instrument privileges.
(d) Additional aircraft type rating. Except as provided under paragraph (d)(6) of this section, a person who applies for an aircraft type rating or an aircraft type rating to be completed concurrently with an aircraft category or class rating—
(1) Must hold or concurrently obtain an appropriate instrument rating, except as provided in paragraph (e) of this section.
Paragraph (e) exempts aircraft incapable of instrument maneuvers and instrument flight from this requirement.
This does mean that you can do the instrument checkride concurrent with the type rating. If your hypothetical PP-ASEL gets typed in a citation, he will end up with a PP-ASEL with instrument airplane rating and the citation type.