Earlier quoted context omitted.
Conservatism is a relative term. You can be a conservative right-winger, a conservative socialist, a conservative liberal or any other kind of conservative as long as your social situation fits it. Many articles by the Economist are conservative in that they intend to defend and conserve the status-quo, especially when dealing with foreign policy.
You're using conservativism vey much in American GOP understanding of the term, which has stopped being conservative a while ago. Conservativism is a relative position, but you can't be a conservative liberal. Economist literally had a massive article what is conservativism. And - SPOILER - UK Torries used to be conservative, while GOP has been reactionary/populist for a while now.
As a relative politico-economic position, conservative is “defense of the position of status quo elites”.
In a society with a capitalist (including most modern mixed) economy, “conservative” in the relative sense is always economically liberal, because the status quo elites in a capitalist society are those empowered by and dependent on economic liberalism for their position.
(“Classical conservativism” is not relative, and is defined relative to the pre-capitalist status quo, and is specifically tends to be about the defense of the titled, landed aristocracy. But, because that is no longer an established elite, there's not a lot of classical conservatism left to defend.)