Small packages like this are key to easily/quickly building polyfill, backport, backcompat bundles for deployment in environments that are quite a bit behind in terms of language support. They still exist and they are still making people money. Having a stdlib in JavaScript would not preclude packages like this due to the afore mentioned legacy environments.
NPM bashing is increasingly popular, and for folks that haven't had to utilize these tiny packages they probably do rightly seem superfluous. Are people abusing it? Probably. Is it being used where it doesn't need to be? Probably. Are there long-stable, rarely changed NPM packages created before `Array.isArray` was a thing, which have this as a transitive dependency? Definitely.
NPM bashing is increasingly popular, and for folks that haven't had to utilize these tiny packages they probably do rightly seem superfluous. Are people abusing it? Probably. Is it being used where it doesn't need to be? Probably. Are there long-stable, rarely changed NPM packages created before `Array.isArray` was a thing, which have this as a transitive dependency? Definitely.