There are some major issues with standardization in BattleTech. First, in other games that have standardized points values or similar, generally have standardized army construction rules, balance by faction, and a fairly standardized sort of terrain rules. Second, in most of those, mobility, terrain, etc, are fairly standardized, and terrain rarely has major impact on the ability to hit or be hit.
And, now, we come to BattleTech:
Maps are not standardized, with maps that are fairly open and maps that have lots of line of sight blocking terrain, partial cover, water, etc, etc that can give one side or another a noticeable advantage. Movement abilities, whether they be inherent fast ground movement, jump capability, MASC and/or superchargers, WiGE or VTOL Movement modes, etc, etc, can significantly impact both offensive and defensive capabilities. A Fire Moth or a Locust, simply because of their speed, can be dangerous on flat terrain, but are even more dangerous when they have terrain they can duck behind when they lose initiative. An assault 'mech of equal battle value is rarely going to be able to have the movement to deny them those advantages, and the ability to hit and fade with high Target Movement Modifiers.
There are no real limits on army construction except what is agreed upon ahead of time. My opponent takes a 3/4 Clan Assault, I take 2 Wraiths at the same Battle Value, guess who is going to come out on top...Hint: Not the Clan Assault. No matter what, someone is going to game the system using pure Battle Value, but, at the same time, players want to use the stuff they like to use. I like Protomechs, another player in my group likes vehicles. I have another known for taking a Panther and hunting Atlases with it. Which is where we come into the final aspect that intereferes with the idea of standardization..
More than the other games, BattleTech depends as much on player skill and knowledge of the game. Sure, 40K and Warmachine, knowledge of tactics and inside knowledge of your army can help you win a battle, knowing the synergies between units, the right stratagems, the right use of Focus, etc, etc can edge out a win...but, in BattleTech, skill matters a lot. Whether it be in predicting what your opponent is going to do, or knowing when to back off, when to cool down, when to press the attack, or a myriad of other things, victory against a more experienced opponent is harder in BattleTech, regardless of what advantages you think you have. Things like making use of the blind spots, presenting less damaged armor? Those can tilt a battle in a way that an less experienced player would not know how to deal with. To make it a fair fight between veteran players and less experienced, Battle Value isn't enough, because it cannot adequately handicap the veterans.
Ultimately, because of this, my group does not use Battle Value. We kinda eye-ball matches to see what looks fair, and, usually, it works out pretty well.