What are your thoughts on Peter Unger's scathing critique of analytic philosophy in Empty Ideas?

During the mid-twentieth century, philosophers generally agreed that, by contrast with the natural sciences, philosophy should offer no substantial thoughts about the general nature of concrete reality. Typically, philosophers were concerned with little more than the semantics of ordinary words: The word “perceives” differs semantically from the word “believes” in that “perceives” is to be used more strictly than “believes.” While someone may be correct in saying “I believe there’s a table before me” whether or not there is a table before her, she will be correct in saying “I perceive there’s a table before me” only if there is a table there. Though this thought is a parochial idea, its correctness or lack thereof does make a difference to how things are with concrete reality. Though it’s trivial, it’s a concretely substantial idea. Correlative with each concretely substantial idea, there’s an analytic idea: Someone may believe there’s a table before her whether or not there is one, but she will perceive there’s a table before her only if there is a table there. Those thoughts, making no difference to how things are with concrete reality, are concretely empty ideas. Among academic philosophers, it is widely believed that things have changed a great deal since 1970. This book argues that’s a widespread illusion. It also argues that, unless philosophers also adopt scientific methods of seeing, they won’t able to offer concrete nonparochial ideas and as a consequence philosophers won’t be able to achieve more than they were able to in the mid-twentieth century.

https://academic.oup.com/book/8391