Can you blame us? This is largely a subjective matter, and the different organizations who talk about this kind of thing have often-conflicting ideologies about how all this works.
When I hear "open source", I don't know which camp the speaker is sitting in. It's perfectly reasonable to get mixed up sometimes.
While it is a subjective matter when looking from the outside, the OSI consortium did a pretty good job of bringing in all of the various groups conventionally referred to as 'open source' and getting the various definitions pinned down in a way that seems to accurately reflect the broad spectrum of possibilities, even to the point that non-open-source companies use their definitions.
While I agree one can still certainly debate the legitimacy of this situation if one so desires, it's pretty much consensus 'within the literature' that the OSI definitions 'are correct' at this pont..
It is a technical term defined by a bunch of people who got together and agreed that their opinions (however educated they may be) are more correct than other people's. That's extremely subjective, and not universally accepted.
Technical terms have definitions that transcend the opinions of people who use them. When I say "byte", everyone knows exactly what I mean, as it's a unit of measurement. When I say "agile", it could mean any number of different things, depending on context. When people say "open source", the thought that comes to a lot of people's minds is simply "I can see the _source_ code, because it's out in the _open_."
It's subjective, and, frankly, annoying. It shouldn't matter how something is licensed, because the most important aspect of software is whether or not it provides value and helps me do my job. Bickering about semantics doesn't get work done.
That's how definitions work.
The fact that you ignore one doesn't make you more thoughtful or insightful it just makes you look like a special snowflake.
Your example is also incorrect because I'll assume you think that a Byte is 8 bits but technically it's not, it's an arrangement of bits a byte can be 0-255bits, it was common to have non 8bit bytes in the past.
The 8 bit byte was set by a specific ISO standard and later by IEEE but it's defined as 8 bits only within those standards.
Agile also has a definition if nothing else because you have bodies and various foundations promoting a specific implementation of it.
Any conflicts that exist are not conflicts in the definition of Open Source, but are different definitions for different terms which is why the terms open-source software and free and open-source software exist.
This isn't a subjective matter, this is a very well defined term, if nothing else because OSS and FOSS software is used in the industry including in commercial products this requires the definitions and the licenses to be very very specific to meet legal and regulatory requirements.
So while you can say there are different software licenses to meet the requirements of being Open Source it needs to meet the definitions set by the OSI which are in general mean that the source code must be available, that the distribution is not restricted in any way which usually means that it's distributed under a free and non-discriminatory license agreement.
You may chose not the follow this definition but this doesn't mean that this is a correct action, this is no more subjective than the definition of a kilogram.
Definitions exist for a reason and that is to remove ambiguity, if ambiguity exists its either because there is no definition or consensus which is clearly not the case with Open Source Software.
When I hear "open source", I don't know which camp the speaker is sitting in. It's perfectly reasonable to get mixed up sometimes.