Yes, language and communication skills play a very big role in increasing the air hostess pay rate. Airlines always look for flight attendants who can connect well with passengers from all over the world. The better you speak and express yourself the higher your chances of getting promotions bonuse and international postings.
Air hostesses represent the airline's image. Clear polite and confident communication creates a positive impression on travelers. Passengers feel safe and respected when the cabin crew speaks to them properly and handles every situation calmly. Because of this airlines are willing to pay more to air hostesses with excellent communication abilities.
Knowing multiple languages is a big advantage. For example international airlines like Qatar Airways Emirates, or Singapore Airlines prefer staff who can speak English plus one or two other languages such as Arabic French or Spanish. A multilingual hostess can serve more routes handle global passengers easily, and therefore earn a higher air hostess pay rate.
With strong language skills you can move up to senior cabin crew or in flight supervisor positions faster. These roles come with added responsibilities and a much higher air hostess pay rate. Many airlines also give language allowances or extra pay for every new language you master.