Worse MRI results....what will happen next?

Does the MRI suggest a cause for the nerve root impingment at L5.
If you are near a university pain clinic, you might consider starting there because they will refer you to a surgeon. Otherwise, (well I would) schedule both.
There may be minimally invasive procedures or surgeries that you could explore. Every answer depends upon cause. Disc bulge is my usual suspect, but there are many other causes.
Consider ablation of the medial branch nerve for the foraminal narrowing at l5-S1.
Don't wait, not because you are in danger, because you are in pain.

My two cents: Go to a neurosurgeon since the principal area of injury/damage is nerve-centered. You describe "moderate spinal canal narrowing" which suggests there may be many steps to progress through before you reach the point of a surgical correction. I'd suggest following all those steps and defer surgery until either (1) You have reached the end of your rope or (2) You have a definitive diagnosis - from a neurosurgeon - that surgical correction is the clear best choice.

My best...

I see my spine physician on Friday - I don't know what type of "surgeon" he is considering referring me to. I've already had numerous Epidural steroid injections, Physical therapy, Acupuncture, Chiropractics, RAF, the MILD procedure, and also had the Sprint PNS System. Looks to me like I really have reached the end of my rope .....

You are the only one who knows when rope's end has been reached. For me the decision was classic "risk management". Which risk was greatest? The risk of continuing to defer surgery which could lead to (1) permanent and uncorrectable nerve damage and/or (2) A painful or damaging fall...vs the risk of surgery where (1) I knew recovery would be long and arduous at times and (2) The ultimate outcome is unknowable pre-surgery, and (3) No surgery is 100% risk free in many ways.

Risk management was a decision framework that helped me. I consulted an Ortho surgeon, a physiatrist, an internist, a neurosurgeon, and a non-medical research scientist (I like pure logical thinking). But keep in mind these experts won't be able to give you an exact answer no matter how much you wish they could!

Best...

I've been in pain for over 10-years. My lumbar spinal stenosis has only gotten worse and now I have pain down my entire (R) leg - making standing, walking and sitting next to impossible at times. Pain is Pain. I've been bounced around between Pain Management physicians and Orthopedic physicians for 10-years and have gotten no relief. I had one Orthopedic surgeon tell me "You are not a candidate for surgery at this time as the risks far outweigh the benefits". Who knows, I may have a new surgeon tell me the same thing when I seem them. But do I really want to live with pain down my entire (R) butt, thigh, and calf for the rest of my life?

I can ditto much of what upstatephil said. I had severe L3, L4 and L5 stenosis with impairment of nerve roots around cauda equina. Only symptom was I had trouble walking for a year, with aches in both buttocks and legs.
Spine surgeon (difference between neurosurgeon and orthopedic surgeon beginning to blur because of current training) said probably only way to get better was surgery, other opinion was I needed to get it done soon to avoid permanent damage.
Again no promises of outcome, it was done first to avoid further damage and secondarily to improve walking and relieve aches.
Six weeks after multiple level fusion, recovery is going well, walking well, virtually no pain, but don't know it ultimately will turn out.
You need a good surgeon, but you sound like you have other medical conditions that make your first surgeon not want to operate

I today don't have the symptoms I had a year ago, and the MRI from a year ago only used the word "MILD".
My current MRI uses the word "Moderate" and "Severe". I have severe pain in my (R) leg, predominantly my butt (making me think I have Piriformis syndrome) and my (R) thigh and calf. The pain is horrible and walking is difficult. I can barely bend to get into a car without a lot of pain. I don't know which type of surgeon my Physiatrist will refer me to when I see him tomorrow, or what that surgeon will say regarding doing any type of surgery. Updates to follow.

I would find a experienced ortho surgeon and get his/her opinion. It appears to me that the L5 nerve impingement may be the problem.. Back in 2018 I developed Sciatica in my left leg with pain all way down to my left foot. I had a endoscopic discectomy at Arizona Spine Institute at L5/S1...Dr. Anthony Yeung. Pain ceased at the knee after 3 months and essentially disappeared after a injection. A follow-up MRI showed a small piece of disc that was missed.

Best of luck. One point of difference in my thinking for you is that, considering you might have some degree of nerve impingement (not uncommon associated with stenosis, I believe) I would want the opinion of a neurosurgeon (nerve expert) vs. an ortho (bone expert). When I ended up in the OR for both neck and lumbar work - a neurosurgeon lead the team which included ortho specialists.

I just met with my spine doctor, a Physiatrist, and his recommendation is for me to contact a Neurosurgeon. He recommended one whose office is right down the road. So I will be contacting this Neurosurgeon to make an appointment.