How often does someone in your team say that? If the answer is “never” or “rarely”, then you may have a problem. It sounds trivial, but it can point to an underlying dysfunction within the team.
If a person never acknowledges a good idea by someone else on the team, that means an idea could shrivel and die. Ideas after all, can be a fragile thing:
“A new idea is delicate. It can be killed by a sneer or a yawn; it can be stabbed to death by a quip and worried to death by a frown on the right man’s brow.” – Ovid
Also, it probably points to something about the person who doesn’t want to acknowledge other’s contributions, or who wants their ideas to be the ones that are taken forward. Working with someone who thinks their ideas are always the best can be tiring and unproductive. “My way or the highway” does not make for an effective team.
Of course, not every idea is going to be a great one. It can be useful to have an “ideation” phase of a meeting, when you generate ideas, then a “refining / prioritisation” phase, where you group similar ideas, and vote on the best.
Ideas being the rebellious scamps they are though, don’t always pop up neatly in meetings. If someone has an idea, and you don’t think it’s a good one, then it’s possible that you may have misunderstood the intention of the speaker. Instead of immediately shooting down the speaker’s notion, try saying something like “That’s interesting, I hadn’t thought of that approach. Could you give me an example of that?”.
That acknowledges the idea, and shows your interest in the concept. If you can think of a scenario where that idea might not work, instead of saying “No, that won’t work. In case X, piece of code Y would would fail.”, say something like “What would happen in case X?”. It asks the proposer to tease out their idea, and they may actually have a solution to that in mind. If not, then the proposer will realise, but they will still feel that their ideas are worth discussing, and are valued within the team.