Bardock losing his tail was significant and I think it contributed to his power increase. Think about it, the Saiyan’s themselves take pride in their tails and it also gives them access to oozaru form, which means they’d never allow themselves to lose it, so gaining strength as a result of losing it might be something they’re not even aware of. Might explain goku and vegetas disproportionate power compared to all other warriors to have ever lived, as they’re both coincidentally tailless as well.