Can you have a drip/overflow pan, that drains out of the room, made for the washer? This is the only real concern one would have, even with a tile floor, because a leak/flood is never good, no matter what.
If you can manage that, I think wood floors should be wonderful.

FWIW, we have wood floors in the kitchen and no drip/flood/overflow pan for sink, DW nor refrigerator. It was not pretty when the icemaker water pipe had a leak where it attaches to back of fridge, but it was a slow one and we caught before damage was too bad. ... living life on the edge with those wood floors .... but I like them and do not want tile.

You should speak with a claims adjuster about just how many rooms can be damaged by a bad leak at a washer...HINT: the damage can encompass 3 or more rooms and a hallway. Putting tile under just the W/D is not making your home "safe" from water damage. My folks had a washer leak that ruined hardwood in 3 rooms and a long hallway. Many thousands of dollars in damage, a lot of inconvenience during the repairs. I'm glad my WD sits in the garage, as does my water heater, which just sprung a leak last week. A loud water alarm alerted us to the water on the floor just moments after the leak began, minimizing problems.

We lived in an apartment house with a washer and dryer in a closet. The floor was cement (new) but the washer was set into a pan with a water bug sensor attached to an alarm. If I had a hardwood floor under the washer, though, I would think about painting it with high gloss paint to seal, if possible.

You can't really seal a hardwood floor, due to the joints between boards. Seasonal movement makes it nigh impossible to expect to own a "waterproof" hardwood floor.

We tiled our w/d area and put a wood transition strip. Its not that high that it should cause a problem.

I hate to be a buzzkill, but my brother had hardwood in his laundry room until the Big Leak. Now it's tile.

We put a high quality vinyl floor in our laundry room, with a water alarm sitting next to the washer. It looks good next to the hardwood it butts up against. Some folks feel that vinyl is a low quality material not worthy of a nice space, but believe me, the new "resilient flooring" is NOT your mother's vinyl. It looks great and does not have the sticky feel to it that the old stuff had. Personally, as much as I love hardwood, (And I do!) I would not take the chance of putting it anywhere with water lines. YMMV, of course. Some GW members are much braver than others! :-)

Cj