[documentation] hyperledger-iroha#3070: mention reduced dev activity

docs/source/index.rst

@@ -4,6 +4,14 @@ Hyperledger Iroha documentation
 
 .. image:: ../image_assets/iroha_logo.png
 
+.. warning::
+    Please note that support for Hyperledger Iroha v1 is limited because it's no longer under active development.
+
+    The core team focuses on `Hyperledger Iroha v2 <https://github.com/hyperledger/iroha/tree/iroha2-dev#hyperledger-iroha>`_, a complete rewrite of Iroha in Rust.
+
+    These versions are incompatible, so you will have to use Iroha 2 instead of Iroha 1 for the new projects.
+    You can read about the differences in the `Iroha 2 documentation <https://hyperledger.github.io/iroha-2-docs/guide/iroha-2.html>`_.
+
 .. warning::
     For secure deployment on platforms other than new Linux versions, please read `this note <deploy/index.html#security-notice>`_ first before deploying Iroha in production.
 
@@ -15,11 +23,6 @@ This documentation will guide you through the installation, deployment, and laun
 
 As Hyperledger Iroha is an open-source project, we will also cover contribution part and explain you a working process.
 
-.. note::
-    Please note that there exists a complete rewrite of Hyperledger Iroha in Rust, `Iroha 2 <https://github.com/hyperledger/iroha/tree/iroha2-dev#hyperledger-iroha>`_. Both projects are developed concurrently in the same repository. However, they are not compatible. You can read about their differences in `Iroha 2 documentation <https://hyperledger.github.io/iroha-2-docs/guide/iroha-2.html>`_.
-
-    For all new projects, we recommend using Iroha 2 instead of Iroha 1.
-
 .. toctree::
     :maxdepth: 2
     :numbered: