Somebody has to take control of ordering the wine in a restaurant, but that person should not necessarily select the wine single-handed.
If you are hosting a gathering, it is perfectly acceptable to take control of the wine list, but defer to anyone who demonstrates an intimate knowledge of the cellar.
When dining à deux, share the responsibility and make the selection a talking point and choose together. Many restaurants helpfully provide descriptions and suggested food pairings. Asking the sommelier for advice is better than pretending you know more than you do and ordering something that isn't suited to what you are eating.
Ordering by the glass can solve the problem of seriously diverging tastes or irreconcilable dinner choices, but it's less convivial and certainly more expensive.