Hi @el-cr. I really like your post. Well done on your dietary shift.
I am a vegetarian that still eats a bit of fish occasional. It is great to hear about your discourse with meat eaters. It is good for people to be open minded and consider the information.

You say, as google does, that: "There is no scientific proof that plants can feel pain".

This is one of my favourite topics of conversation :)
Of course, plants do not feel pain the same way as an animal. However they are conscious living beings and they feel pain and love in their own way and they should be kept and killed responsibly.

All the best evidence is in the documentary film "The Secret Life of Plants" released with the album Stevie Wonder's Journey Through "The Secret Life of Plants" in 1979.
In this film they show the amazing work of Jagadish Chandra Bose who hypothesized that plants "feel pain, understand affection, etc" in 1902. He was thrown out of The Royal Society in London just for daring to suggest it. In 1966 Cleve Baxter demonstrated using polygraph electrodes that, not only do plants react to damaging events like fire, they react telepathically to someone thinking of burning them or to any damage of surrounding plants.

Thanks again, be safe.