Laser Resurfacing or Pinch Excision for Loose Skin on Eyelids?

As always, each case is individual and the treatment plan should be customized for each patient after careful evaluation and discussion with your surgeon. In general, laser resurfacing ( I prefer fractional lasers such as the Active and Deep F/X) is used to smooth out wrinkled skin. The CO2 fractional lasers have the advantage of creating more collagenesis because of the thermal (heat) component of the laser. Of course, it is limited because the surgeon is not removing skin or muscle. A transconjunctival lower lid blepharoplasty plus a laser is a great option for rejuvenating that area. Conversely, if there is a significant muscle roll, laxity of the lower lid tendon, or a lot of redundant skin, then an external incisional blepharoplasty is indicated in order to access these structures to tighten and/or remove them. Thank you.

Your surgeons feel you are pre-disposed to ectropion-you are fortunate that you were examined by doctors who knew the risk and did not operate on you.
In a person pre disposed to ectropion or lid droop after blepharoplasty, both pinch excision and laser resurfacing could cause an ectropion. Even a transconjunctival blepharoplasty should be done cautiously.
If your surgeon is comfortable doing a canthoplasty to tighten the lower eyelid then the risk of ectropion is lessened. In that situation a transconjunctival blepharoplasty and fractional ERBIUM ablative laser resurfacing is your best option to tighten eyelid skin.
I would avoid CO2 laser-flat beam or fractional (Fraxel, activeFX) because the CO2 is much more likely to result in ectropion than the Erbium laser.

That is a difficult question to answer without examining you.  If your skin problem is treatable with laser, then, in general, I would prefer that route.  However, complications related to lower lid drooping is also possible from either laser resurfacing or "pinch" excision.  You need to make sure that you are a good candidate for those procedures as well.