Statistically speaking, yes, it helps.
My understanding is that it might not help with your specific devices until there is a Sense-wide device model that establishes itself with sufficient statistical confidence … and at that point the device model (signature) would still have to emerge from your mains electrical waveform, i.e. “match” … before (I suspect) Sense might go looking in the device list you’ve entered. Do not think of it as “I entered the device make and model so why isn’t my Sense hunting for it?”
For devices that Sense finds and names auto-magically, the make/model you designate there certainly gets back to the Sense team and can help them with refining the ML to match particular device types and, ultimately, models. Think of that as more like “It’s a 4kW water heater vs a 2kW model” than “It’s a white fridge vs stainless steel”.