yes it is ðÂÂÂ

they do love bright light which is well provided as per you photo
i saw people support them with sticks to keep them upright !

Dieffenbachia. Rotating the pot often can help keep it upright. When plants do not have wind blowing on them, their stems/trunks can be less sturdy. If you try to straighten these, they might break, I would probably cut them off near the soil line and use the pretty tips for cuttings. New growth should also come from the stumps.

Thank you! If I were to cut it, I've read that there are several ways to grow the cuttings such as replanting in moist soil, placing in water, or even laying horizontally atop moist soil. Which way seems to be most effective?

Each of those methods has ardent proponents. Looks like you have enough material to try any/all that sound like fun to you. (Just keep track of which end is which, if trying any pieces of naked stem with no leaves.) Do you need a dozen new plants? Probably not, but you might use them to trade for other plants, or give as gifts. I usually just stick cuttings back in the pot with the mama, which I consider most effective, but at some point, it'll be too full. Then you can go to a bigger pot, or separate some to separate pots.

Has this plant had a change of soil since you've had it?