Sometimes when I buy non-led lamps for my collection, people tell me to buy the led equivalents. When I say that it's for my collection, they ask me 'why use these old lights, leds are much more capable and flexible'. What is the response to this? (I can already see Ria's rant)

I would just say "I don't like LED", even though I do use LED extensively for downlighting, which is probably it's best general lighting application because of how directional the lamps are compared to incandescent.
But for everything else I use fluorescent and metal halide (I even converted a light fixture from magnetic RS F40T12 to electronic programmed start F32T8 earlier today because I wanted more light ). I do not use incandescent lamps because they use too much energy and get too hot for me.

If someone doesn't understand, compare it to a pianist who prefers an acoustic piano over an electronic. Many people wouldn't be able to hear the difference in a blind test, and electronic pianos have definite benefits over acoustic ones. But still, many enthousiasts prefer a real grand piano over the electronic one despite all the cost and maintenance that comes with it.

Sometimes when I buy non-led lamps for my collection, people tell me to buy the led equivalents. When I say that it's for my collection, they ask me 'why use these old lights, leds are much more capable and flexible'. What is the response to this? (I can already see Ria's rant)

A proper response is just do not waste your time in empty discussions, and don't get pulled into manipulative talks. You come to get an *exact* kind of light source you need right now, be it a kerosene lamp or led. If the seller has it, right, here is the money. If they don't, just goodbye.
 

Yeah, I think that's the easiest answer, just mention you prefer the older lamps and leave the conversion at that. 

Sometimes when I buy non-led lamps for my collection, people tell me to buy the led equivalents. When I say that it's for my collection, they ask me 'why use these old lights, leds are much more capable and flexible'. What is the response to this? (I can already see Ria's rant)

Rant..? Who, me..? 

Presumably where you live, you've got the option of what to buy, but here, unless you go online to eBay or similar places, there's nothing, and even there, the choices are diminishing. Retail, it's LED or if you don't like that, LED 
And that removal of choice is my primary reason for refusing to use LED. I'm a contrary old (insert your own choice of word here ) and I don't like being forced into doing or not doing something 

Ok, rant over, back to whatever it was you were talking about 

If someone doesn't understand, compare it to a pianist who prefers an acoustic piano over an electronic. Many people wouldn't be able to hear the difference in a blind test, and electronic pianos have definite benefits over acoustic ones. But still, many enthusiasts prefer a real grand piano over the electronic one despite all the cost and maintenance that comes with it.

That's the best analogy I've heard in a long time. 
Thank you.! 👏 👏 👏

Most shopkeepers will be happy that somebody bought their non-led stock that nobody else wants. Other people will complain...

That's if they're still allowed to sell it, which isn't the case everywhere