What are your thoughts? Will "De-Fi" become popular on Bitcoin as ETH's fees rise all the way to the moon? Or will smart contracts on Bitcoin become a "failed experiment"? Your input will be greatly appreciated. Thanks in advance.

Nope, don't think Bitcoin developers are interested in those bullshit as that's what they're. Bitcoin is the best defi project you can see in the space, why then do it have to give opportunity to project that won't have been able to stand on their own to used the influence of bitcoin to hyped themselves and probably scam millions off the market.
Bitcoin can't start competing with ethereum to be the head of a concepts that has failed. Bitcoin has never been hacked successfully, the only exploit that happened years back when the network was still new was handled perfect without any lose been recorded unlike the uncountable hacked occuring almost monthly on the defi platforms.
Some platforms even gets exploited more than ones. If ethereum fails which the fees are already showing, we have others blockchain that'll step up to replace ethereum like tron etc.