There's always a tradeoff. By describing our company as "alternative to X" you saving tons of time by explaining what you company does. People are overloaded with information, and average attention span very short. But I see the disadvantages too! We have an internal debate about tagline a few months ago, and essentially decided to go with "Open-source alternative to Segment". But it wasn't an easy decision!
However, I think that the product matters the most. You can change the tagline in a few clicks. Can't say the same about the product