Background: (Proper galvanic isolation, e.g. opto-isolation, isolation transformer, etc., is assumed for the question)
When working with 110/220AC, switching elements are typically relays (solid state and electro-mechanical) or triacs/thyristors. Doing AC power control requires phase angle detection and zero crossing switching. Less frequently I've seen rectification+MOSFET as a control strategy. A previous question here links an Instructables tutorial which implements a possible DC switching method.
Both share some disadvantages, like any time an AC supply is switched, power factor is affected. Advances in MOSFET technology mean that prices for high-voltage transistors have evened out.
Question: For loads that are compatible*, what are some reasons against "rectify AC and use a high voltage MOSFET" and favor "triac phase angle control with zero crossing detection"?
*Some AC loads also function on DC: resistive bulbs or heating elements, universal motors, etc. and therefore maintaining AC is not a requirement. Assume higher non-RMS voltage is not an issue.
Side note: I'm analyzing different strategies for controlling heating elements in a SMD reflow oven-style device.