Yes, many are muted. I’ve never seen this Thailand species before, either. The ones in India are also muted, although the red-vented bulbul has its sassy flash of red below the tail. 😉 I’m sure we’ve posted that species several times here if you do a quick search. Thanks again, as always, for your comments!
Organikos 
What a unique beauty with interesting coloring! I remember seeing many bulbuls when birding in Israel, but they were all muted colors, as I recall.
Yes, many are muted. I’ve never seen this Thailand species before, either. The ones in India are also muted, although the red-vented bulbul has its sassy flash of red below the tail. 😉 I’m sure we’ve posted that species several times here if you do a quick search. Thanks again, as always, for your comments!
I actually did look back at some of your previous images of the bulbuls … right after I posted my comment. 😉 very cool!!