This is a mistranslation of the Latin, infernos, and the Greek katotatos, meaning the depths (of the earth). There is certainly no reference to a place of posthumous punishment. From the 3rd century interpreters invented the mighty drama of the Harrowing of Hell in which Jesus liberates the saints of the pre-Christian era from the power of Satan. That is a fine piece of theology, but it may have nothing to do with the Creed as such. Of course if one translates accurately one is left with the question, what was he doing in the depths of the earth? It must mean something more than just being dead.
Can it refer to Hades, the classical place of the dead, described by Homer as “the after-images of used-up men”? The Hebrew word Sheol also refers to a realm of shades. This would envisage Jesus sharing the uselessness of the dead, their lack of agency.
1st Letter of Peter 3 mentions “Christ announcing the gospel to the spirits in prison.” Nobody knows for certain what this means, but it may have contributed to the development of notions of his ministry after death. In any case more general statements by Paul make it clear that no dimension of the cosmos, and therefore no person, is left untouched by the death and resurrection of Jesus.
Me? I like the notion of the “harrowing of hell” which is truly evangelical, meaning that even in hell the good news is announced by Jesus, and that souls can respond. This is probably not very orthodox, as hell is excluded from Hope, but I like to think that may be a mistake.