is that good or bad?
I wouldn't say it is either. It's just how the checksum works.
that really doesn't seem ideal. it makes me wonder about this whole checksum thing and if it's really all that important or just a gimmick.
That's because we are considering it backwards here. There are only 128 possible words if you are picking them manually. Since the last word of a 12 word seed phrase also contains 7 bits of entropy, then when generated properly there is exactly one word which provides the correct checksum for the provided entropy.
And yes, it is important. If you don't have a checksum and import an ncorrect seed phrase, then you have no idea you have imported an incorrect seed phrase. You could spend weeks or months trying to brute force a passphrase which doesn't exist, or searching weird and wonderful derivation paths, or who knows what else, trying to hunt down your wallet. With a checksum, you know immediately one of your words is wrong and can immediately narrow down your search significantly. Not to mention that brute forcing an incorrect seed phrase is also quicker with a checksum since you do not have to derive addresses and check them for balance for all the invalid phrases.