IMO, it is not
I'm considering 3 types of rim.
All three material types do not lend themselves to flexibility. The brittle nature of the material would crack, perhaps not even visibly.
But, I have to be honest here
I have straightened cast motorcycle wheels using a small jack and a propane torch to heat it up. I also had a truing stand.
The procedure looks like this and that's about how bad my rim was when I did this. I will add, I was VERY young and very broke and didn't consider consequences to actions. That being said. The wheel lasted another two years, when I sold the bike I told the new owner, "get a new rim because this is what I did."
That rim was unpainted and I inspected it with a jewelers loop to look for cracks, did not find any before or after but I have always believed that were microscopic fissures in the rim. I have no proof if that belief is truly a fact.
I simply heated up the area around the bend with the propane torch making sure I didn't linger too much in any one area. I was not trying to melt anything or pool up any of the, in my case, cast rim. I was simply making it more pliable.
The rim can soak up a lot of heat and distribute it quickly around the rim as it's aluminium so I set it in the sun for a bit to get up to around 130 degrees F first.
I used the jack to slowly push out the bend and would then put it on my truing stand to check for fault. I did a wash, rinse, repeat of this quite a few times before I got it right. I used blocks of wood to prevent scarring of the rim.
This is what it looked like. I don't recommend this. I never felt good about it. I have had peers validate the solution but at the end of the day, none of us are metallurgists.
Here was my tool list