It is. But, the Rio en Medio trail from Chupadero is overwhelmed. I went twice, both times on Sunday morning, both times, no parking. The first time was a traffic jam with a driver who couldn't turn around (there are no spots) or, steer in reverse. The last time, there were signs about the number of parking citations given for each of the last seven days. There is only about seven legitimate parking spots there.
I would consider the approach from Aspen Ranch, or the Nordic Ski Loop off of 475. Or, park before daylight, planning on someone else doing a bad parking job.
Pretty much anything along NM475 is quite reasonable during the last few weeks. Big Tesuque campground is/was parkable, and there is a nice one about twenty minutes hike downstream, on an informal trail, from there, before the south fork confluence. Also, the bushwack from the Borrego Trail crossing going upstream to the lower falls isn't half bad, there is better GPS coverage in that canyon then I get in town. I wear leather gloves on those hikes, because the ground is unstable, and I typically have to break a fall at some point.
Most of the time that I visit, I skip Little Chasm, that was before all of the upper Pecos watershed parking facilities were roped off.