为何用虚拟语气

If I had to makejust one recommendation for where to stay in Rome, it would be Yellow Hostel. It’s one ofthe best-rated hostels in the city, and for good reason. It’s affordable, andit’s got a fun atmosphere without being too noisy. As an added bonus, it’sclose to the main train station.

上面一段摘自2021年新高考考试英语全国卷I的阅读理解A。请问第一句为何用虚拟语气？

If I had to makejust one recommendation for where to stay in Rome, it would be Yellow Hostel. 假如必须要我对在罗马的住宿作个推荐，那就是黄色旅馆。

非常显然这里提出的假设不是事实，无人要你必须要作个推荐，所以用了虚拟语气。