I don't think it is fair to say that there was ever 100% agreement over what some of those terms meant.

Like or hate it, language means what the people think it means, and as GP suggests, choosing terms that disambiguate differences is a far better approach that allows people to find common ground rather than have a knee-jerk reaction to a policy because they associate with one ambiguous label and are told that the policy is associated with another.

Adding more dimensions to the policy spectrum help. One dimension (left/right) covering all manner of social and economic policy leads to confusing outcomes.

A two dimensional view - economic left-right on one axis, and libertarian/authoritarian - is one view that is popular now, so giving four quadrants, left lib, right lib, left auth, right auth - and that is already a lot more granular. With any quadrant view of course, the dispute is always going to be where the centre is... it is something of an Overton window, where extremists try to push in one direction to shift the Overton window and make positions that were firmly in one quadrant seem like the centre.

However, there are other dimensions as well that could make sense to evaluate policy (and political viewpoints) on even within these axes. One is short-term / long-term: at one extreme, does the position discount the future for the benefit of people right now, and at the other extreme, focusing far into the future with minimal concerns for people now. Another could be nationalist / globalist - does the position embody 'think global, act local', or does it aim to serve the local population to the detriment of global populations?

That is already a four-dimensional scheme (there could be more), and I believe that while real-world political parties often correlate some of those axes and extremes on one are often found together with extremes on another, they are actually near-orthogonal and it would be theoretically possible to be at each of the 16 possible points near the edges of that scheme.

That said, even though they are almost orthogonal, an extreme on one might prevent an extreme on another axis in some cases. For example, I'd consider myself fairly economically left, fairly socially libertarian, fairly far towards favouring the long term over the short term, and fairly far towards globalist (think global, act local) thinking. But some would say that an extreme left position requires no private ownership of the means of production. In the modern world, a computer is a means of production. I would not support a world in which there is no private ownership of computers, because that counters my the social libertarian position. So, I draw the line at wanting public ownership of natural monopolies and large-scale production - I would still want to live in a pluralistic society where people can try to create new means of production (providing it doesn't interfere with others or the future, e.g. through pollution, safety risks, not paying a living wage, etc...), rather than one where someone like Trofim Lysenko has the ear of the leader and no one can disagree no matter how stupid their beliefs are. But I'd want to see the ability for the state to take over those new means of production in the public interest eventually if they pan out and become large scale (and for research to happen in parallel by the state).

I think putting one's viewpoint on multiple dimensions makes it far clearer what someone believes, and where there is common ground, compared to picking labels with contested meaning and attacking the other labels.