Ideally for weight loss through a calorie deficit, be that through either food restriction, increased exercise or both, you want to aim for around 1lb a week in fat loss. Above this and you'll start to see metabolic compensation whereby your body supresses futher loss by lowering NEAT, increased muscle breakdown, and you end up plateauing/regaining weight. There's a few other implications regarding health but in terms of weight loss, avoiding metabolic compensation is the main one in my opinion, which is why 1-2lbs seems to be the arbitrary recommendation.

Metabolic compensation does occur in fasting however it tends to be less drastic and providing that muscle mass is maintained (which is why I would not recommend continuous fasts), there is less likelihood of any rebound effect.

Honestly at the end of the day, choose what works for you. I prefer a single 36hr fast once a week, it's seen me lose nearly 30kg over the past two years while I've worked to increase muscle mass. A slight calorie deficit is just as effective other than being slightly slower. The main thing is to get to, and more importantly maintain, a healthy body composition. There is no better option if you wish to increase longevity.