Metadata (and initial body text) tweak to "what is a service mesh" pa…

…ge (#1758)

Signed-off-by: Flynn <[email protected]>

linkerd.io/content/what-is-a-service-mesh/_index.md

@@ -1,5 +1,6 @@
 ---
 title: What is a service mesh?
+description: A service mesh adds security, reliability, and observability features to cloud native apps by transparently inserting this functionality at the platform layer.
 enableFAQSchema: true
 aliases:
   - priority = 1.0
@@ -31,11 +32,11 @@ faqs:
       present but taken for granted and not actually given too much attention.
 ---
 
-tl;dr: A service mesh like Linkerd is a tool for adding observability,
-security, and reliability features to "cloud native" applications by
-transparently inserting this functionality at the platform layer rather than
-the application layer. The service mesh is rapidly becoming a standard part of
-the cloud native stack, especially for Kubernetes adopters.
+A service mesh like Linkerd is a tool for adding security, reliability, and
+observability features to cloud native applications by transparently inserting
+this functionality at the platform layer rather than the application layer.
+The service mesh is rapidly becoming a standard part of the cloud native
+stack, especially for Kubernetes adopters.
 
 Over the past few years, the service mesh has risen from relative obscurity to
 become a standard component of the cloud native stack. Linkerd ("linker-dee"),