I can access the administration portals for each, but when I view our website I get a "error:server refused connection" message in the embedded iframe.

According to the status report all services are "up"

https://status.zoho.com/

However, the response time and transaction time for many services has greatly increased.

Is this caused by a known issue?

Zoho Survey Response Time

Zoho SalesIQ Response Time

Zoho Support Response Time