Should place names be changed?

I saw video clip yesterday from BBC Cymru Wales in which someone called Tudur Owen talks about the way in which Welsh place names are being slowly replaced with "easier to pronounce" English names. He also talks about the way in which, by replacing these names, history and stories are being lost.'
It seems to me that an entire culture is in danger of being lost - not just there but in other places and in other ways as well.
     "Move with the times!" Did I just hear you shout that?
Well, sorry but I am going to remain stuck fast.
There was a point where we nearly lost Scots Gaelic, the language of my ancestors. My paternal great-grandparents spoke Gaelic. My paternal grandfather knew only a little. His son, the Senior Cat, knows none at all. I know only a little. I am entirely self taught. I have almost no idea how to pronounce what little I can read. There is nowhere here for me to even begin to learn the language. 
      "It's a dying language!"  Yes, I heard you shout that too. You are wrong of course. It is making a slow, painful recovery from being beaten almost to death by people who believed (and still believe) that they know better. They will tell you that English is easier to pronounce, easier to learn, easier to this and that and something else. They will tell you that English is the world language and that there isn't any need for anything else.
Sorry, you are wrong. English is a very important language but it is by no means the only language on the planet. Those apparently dying languages are still important, very important. They carry with them an entire culture and all the thought processes which go with that culture. Every time we lose a language we lose a way of thinking. Losing a way of thinking matters. It matters not just to literature, music, art and theatre but to humanity as a whole. It matters because each language brings with it a set of moral values and ways of understanding the world that further human development. 
I don't know a lot about Welsh but I do know enough about the "mutations" to use a dictionary. "Mutations" are changes at the beginning of a word rather than the end of it.  They occur in other languages - such as Swahili - too.
In the same way I know something about prefixes in Bahasa Indonesian  and some of our local indigenous languages. It's the way those languages have developed and the way they still work.
Yes, I have an interest in languages. My working life still revolves around the need to know not the languages themselves but about them and the way they work. I have had to learn more than most people and I don't expect others to be able to do that any more than a  surgeon would expect me to be able to perform an appendectomy. 
But that doesn't mean that you should expect people to give up their language and their culture and their way of thinking simply because you believe their minority language is "difficult". It is no more difficult than some sounds in French, Portuguese, Arabic or Chinese. Nobody is suggesting that those languages should cease to exist because English speakers find them "difficult".
Let's keep Scots Gaelic and Welsh and other such languages alive. They have magnificent literary and cultural traditions from which we can learn a lot. We will be better humans because of it.