Is Veuve Clicquot Brut a good champagne?

It is a mass-market Champagne. Easily available all over the world. Quality is pretty standard in its price range. So, there is nothing wrong with buying it. It is absolutely okay to give it as a present.

There are mass-market Champagnes, the big brands which everybody knows. Standard quality, some are slightly better than others. Price range: € 29–40. Some examples: Lanson (often a good bet), Piper-Heidsick (also good value for money), Laurent Perrier (one of my favourites), Taittinger, Moet & Chandon, Veuve Cliquot, Bollinger, Pol Roger, Perrier Jouet, G.H. Mumm, Roederer…

There are cheapish products with unknown names or fantasy names (like Grand Plaisir). Most of them are not recommendable. Price range: € 15–25. Better take a good crémant instead.

Over 3,000 Private Credit Deals From Just 20 Analysts Raise Questions on Wall Street - Bloomberg.com

There are Champagnes from small, family-owned wineries. They are usually the best bets, but you have to know them. Often you have to import them directly. Price range: € 18–25.

There are several layers of price/quality of Champagne:

There are luxury Champagnes which are also produced by the big mass-market wineries: Ruinart (somewhat in between standard and luxury quality), Dom Perignon, Roederer Crystal, Krug…

That whole wheat bread you've been eating is often a trap - it's not what you think it is - Earth.com

I personally do not buy it because I know alternatives which have better value for money. But when I am in a store, say in Central Africa, and there is nothing else available I would take it.