No. What "you" (plural) are saying is that it's perfectly acceptable to have CE druid riding around on motorbikes with flame throwers burning Bambi and Thumper because there are no explicit rules against that. Any DM who punishes that type of activity is a tyrant on a railroad.
Yes, chaotic evil is a perfectly acceptable alignment for Druids, just as it is for any other class, including Clerics and Paladins. If it wasn't they wouldn't have the option. 2 out of 5 of the Nature deities available in the 5E Forgotten Realms pantheon are evil, one of which is Chaotic Evil, and both evil options are available for worship of either Druids or Clerics. Also, Druids are known to be allowed to use any metal items they want, hence having the option of a selection of metal weapons, and the freedom to gain proficiency in any metal weapons they wish. The only prohibition is on armor, so yes, they could ride around on motorbikes, just as they could ride in a metal carriage or swing a giant metal hammer. This isn't just a "Druids should be able to do this" dialogue; the rules explicitly allow it.
For example, the Forgotten Realms Pantheon includes Auril, goddess of winter. Auril is one of the 5 nature deities, who can be the source of power for either Clerics or Druids. The dogma of this deity is to cover all land with ice, quench fire wherever it is found, and to work darkness to hide the sun so that the chill of Auril may slay. She orders to kill arctic creatures only in great need, but to slay all other life. The only taboo on the scenario you explained that a Druid of Auril would suffer would be to not use a flamethrower, but I'm sure she'd love some cold steel blades or some kind of magical frost-thrower. Bambi and Thumper? They better be wearing their coats, else Druids of Auril are fully expected to kill them on sight. If that Druid of Auril happens to be of a druidic sect similar to the Children of Winter of Eberron, who venerate death, then Bambi and Thumper better be twice as careful crossing their path.