Yes, in the sense that an investment-linked policy (ILP) has no guaranteed return: its value follows the sub-funds you choose and can fall as well as rise. A guaranteed endowment plan has a contractual guaranteed part. They are built for different jobs, so risk is only one part of the comparison.
Where the risk sits
In an ILP your premiums buy units in investment sub-funds, so the value follows the prices of those funds and you carry the market risk. In an endowment plan the guaranteed part is the insurer's obligation. A participating plan adds a bonus that is not guaranteed.
Costs differ too
An ILP charges for the funds and for the policy, and those charges come out every year whether or not the funds do well. See how much the charges cost over time.
Different jobs
An endowment plan tends to suit a defined goal and a fixed date. An ILP is a way of investing through an insurance wrapper, usually with a longer horizon. Read the longer comparison in the ILP vs endowment guide.