No, the 3600 does not support 802.11ac. You need at least the 3800 for that.
The 3600 is almost five years old, since it was released in Apr 2016. While it's still supported, it is lacking processing power and might feel a bit sluggish. Unless you already have a 3600, I'd recommend looking for the latest version, which is the Roku Streaming Stick+ (3810). it also has an improved WiFi antenna (part of the power cord) and more memory for channel storage and the operating system.
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