I am looking for a LED ceiling lamp that should have at least the following characteristics:
warm white light
luminous flux at least 2500lm
flux gradually dimmable via rotary dimmer switch in the wall (no remote control), dimmer and lamp can be separate products
After some research I could not find such a model so far. Either the dimming works only via remote control, or the lamp is not bright enough or the dimmer switch is only adjustable in steps (usually it is a 3 way switch).
You are stuck in “appliance mode”. You really need to separate out into:
Light Fixture
plus
Switch
In the old days it was simple. A light fixture was a gadget that held some sort of bulb(s) – regular incandescent, candelabra incandescent, fluorescent tube. And later some additional types – various halogen types, etc.
If you wanted anything fancier than on/off it had to be done at the same switch that handled on/off. Dimmer, timer, motion sensor, etc.
Now there are “smart fixtures” and “smart bulbs”. An example of a smart fixture (to some degree) is a ceiling fan/light with a wireless remote control. The wireless remote can turn the light on/off and dim it, and it can turn the fan on/off and adjust the speed. Sounds great, right? Until you lose the remote. Or someone turns off the switch on the other side of the room (3-way switches are quite common for a light fixture in a large room…that gets replaced with a fan/light) that you had either never known what it was (and neither does the person who turned it off, because the fan and light were off at the time) or that you stuck a piece of tape on it “don’t touch this” (I grew up in a house with a timer on a 3-way switch like that). Etc.
So “smart fixtures” are not always so smart.
“Smart bulbs”? Even worse. Often designed to be controlled via WiFi. What happens when the router is replaced or the WiFi Key is changed? What about guests who have no clue how to get it to work? Etc.
The solution is simple:
Light Fixture
Pick a fixture which has the light qualities you want (warm white, 2500 lm, dimmable) or that takes bulbs and get bulbs that match the light qualities you want. That should be trivially easy to find.
Switch
Get a switch that has the capabilities you want. That would include an LED-compatible dimmer. It may include other functions such as timer or WiFi control or motion sensor. But the bottom line is that it is a switch. So you can press it or toggle it to get the light to turn on and off.
Then if you want more light you replace the fixture. If you want more other features you replace the switch. But they are two separate things. Not a package deal.