New pipelines can and will be built, Russia will sell its entire supply of gas to China, Turkey, Hungry, India, all of South American and other countries not supporting the sanctions.
As long as the world economy runs on fossil fuels, which it will for the next few decades, Russia will never be without customers for its gas/oil, keep sanctioning them and removing their products from the world markets will has already driven prices up 4-fold and Russia will continue to make as much or more revenue even if sales drop.
You combine the sanctions with the Green Energy idiocy of the Western World and Russia will be a major player in world markets for a really long time.
“Russia can sell all the gas it wants to other countries that have not sanctioned them”
Hope is not a plan of action.
The actual big projects that they had planned to expand their capacity to other markets, the Power of Siberia 2 pipeline, and the Arctic 2 LNG terminal; were not on track to go operational until 2030.
Both of those projects had their finances and partners pull out since the war.
It took decades to build the gas pipeline network to Europe. Replacement for gas customers is a long way away.