The 3# pistol is not obsolete, but it may not be best suited as an EDC firearm. That has to be an individual decision.
Between LE on-duty and off, and now retirement, I have carried since '64. In this period I have carried many different revolvers and pistols. There has always been a dichotomy between power/capacity/weight/shootability vs portability/comfort/concealability.
During my career we were required to respond, even off duty, regardless of jurisdiction, in any situation requiring law enforcement intervention. That meant CCW, even though that was not spelled out. What it did accomplish was to force each of us to resolve the various disparate carry issues so that we would in fact be armed.
The challenge is and has been to find a suitable compromise. Fortunately in today's market there are more choices than there have ever been before.
I find any recommendation to just lift weights to be a useless platitude. People who don't lift weights or work out are not going to start now, just to be able to carry a heavy or heavier handgun.
My entire adult life I have lifted weights. At my peak I could bench press over 400#. Even at my advanced age, I still work out, although now with a weight machine rather than Olympic weights. Through all of this, regardless of how much I could lift, I was always seeking that elusive ideal combination of firepower and ergonomics.
Since I was a power lifter, I have had many people approach me who wanted to start weight programs. The first thing I would tell them was that unless they were absolutely determined to stick with it, don't even start. Very few had that determination.
For me, since around 2000, the ideal compromise in one handgun has been the Glock 26.
Note: This is not a plug for Glock. I am one individual relating my preference based on my experience for the purpose of illustrating an example.
For me the Glock gives me the best compromise I have found between power, capacity, shootability, reliability, comfort and concealment.
That does not mean it is the ideal compromise for anyone else. Each of us needs to make that determination on their own.
If someone has a 3# pistol that they are willing to carry and properly conceal, then for that individual it is not obsolete. But if one makes that decision, then one also needs to commit to not finding excuses to not carry. This is a long-term decision. One may start with the best of intentions, but as the novelty of CCW wears off, and the practicalities of everyday life take precedence, that commitment may be sorely tested.
This discussion is one I initiated in every Calif state mandated CCW course I taught, because everyone will confront this issue and to resolve it. I always concluded by citing the parachute rule: 'If once you need it, and you don't have it, you probably won't ever need it again'.