Helo, Debra-Rowlands a croeso i’r ffwrm! (and welcome to the forum!). I’m a bit late to this discussion. I live in the United States and that’s my excuse. HA! I won’t add to the impressive answers previously given. But obviously to this group, learning/speaking Welsh is very important and NOT a waste of tlime/energy. It’s also important to you, or you would not have asked the question.
My first thought after having read your question was to ask, “Why does that person think it’s a waste of time?” I’d be interested to hear the answer. It seems to me there are a lot of stupid stereotypes regarding the Welsh and the language that are persistent, i.e. “It’s an antiquated language…” “no one of significance speaks it…” “Only those of lower class speak Welsh…” “If it had value, the English would use it…” “If it’s so important why does only 20% of the population speak it…” and many more. It’s important to you, that’s all that should matter. But I also understand the need for approval from those we care about. I highly value my Wife’s opinion and when she disagrees with me, I take her concerns seriously, which leads to discussion.
Why does this person believe Welsh is a waste of time? I wonder what would happen if you said, “I don’t see it that way. How come you believe that?” This should lead to an interesting discussion.
If I was neglecting my familial duties, like, "I will, yeah! I’m trying to conjugate “bod,” then I need to readjust my priorities. But otherwise, it’s your time. Do what you want.