My argument is that "Liberalism" is more akin to a domain of politics, such as "Leftwing", than to an actual Political Ideology such as "Socialism".

This is also consistent with the idea that there is a Freedom - Control political axis which is separate from the Left - Right political axis: Liberalism is basically being towards the Freedom side in that axis.

This means that you can't claim there is a real Liberal political ideology and that the various political ideologies which are deemed Liberal are not really Liberal because they're different things: Liberalism is a group of political ideologies defined around freedom and there is no such thing as "the one true implementation of it" because that's not a recipe, just a set of ideas which when combined in different ways and quantities (and, as I think we've both concluded in our discussion here, some of those liberal ideas don't play nice with others or in other words, some freedoms go against other freedoms), give rise to various different Liberal political ideologies.

So you (or whomever started this by pulling out that Wikipedia definition) are absolutely right in saying that the definition presented there is Liberalism and that the people who follow it are Liberals, what IMHO you are wrong in is in claiming that present day Liberals aren't following the "real" Liberalism: if there's one thing made clear from our discussion is that modern political ideologies which implement those ideas in whatever combination and orders and quantities (the examples I've been mainly talking about being those which put Property Rights above Liberty, such as Neoliberalism) are in fact Liberal since the political ideology they follow is a specific implementation of Liberalism.

So yeah, to wrap up the entire discussion, people who believe in modern ultra-capitalist hard-neoliberalism were Property Rights in the most trump Liberty are in fact Liberals -because the most hardcore and capitalist neoliberalism is made up from a specific combination of the principles of Liberalism - but then so are people who believe in Social Democracy because that political ideology too is made up from a (very different) combination of the principles of Liberalism.

This does mean that some Liberals are not in fact hard-right and can even be Leftwing (if, for example, they believe in Social Democracy), but in the present day most Liberals are hard-right because amongst the political ideologies that are made from the principles of Liberalism, Neoliberalism is much more dominant than Social Democracy.