Careful. The venn diagram bubble depicting your statement overlaps heavily with the anti-vaccine bubble.
Its a bit naieve to claim that cleaning one's home will result in an extinction of enough microbes so as to be threatening to our immune system.
Nothing strengthens an immune system like a weekly furry party or attending "tough mudders" events.
That’s because the parent claim is known as the hygiene hypothesis and has been disproven by science, in common with anti vaccine claims. The immune system has not been shown to benefit from training, but has been shown to be damaged by illness.
Thank you! I wish I could upvote this twice, fellow redditor!
See: Polio
https://en.wikipedia.org/wiki/History_of_polio
> [...] Better hygiene meant that infants and young children had fewer opportunities to encounter and develop immunity to polio. Exposure to poliovirus was therefore delayed until late childhood or adult life, when it was more likely to take the paralytic form.[22]