Did larger blocks ever become popular, since the BTC, BCH split?

At least on the Ethereum ecosystem, it has been increasing slowly until last year. See "Ethereum Mainnet: Historical TPS Capacity" [TPS = transactions per second] graph here: https://www.growthepie.com/quick-bites/ethereum-scaling

Since launch, Ethereum Mainnet has methodically improved efficiency and capacity without compromising decentralization or security. It went through several key upgrades, each contributing to incremental improvements in efficiency and capacity. You can read more about these on our ecosystem page. From 2015 to today, Ethereum scaled from ~0.71 TPS to 24.9 TPS, a 35.0x increase.

After years of steady gains, the pace is set to accelerate. The goal is to scale by ~3x per year with upcoming improvements. This takes today's 24.9 TPS into the thousands before decade's end.

There are many other upgrades yet to come. You can also find more details about them here: https://forkcast.org/

But the scaling approach also changed. We are no longer just looking for vertical scaling, like larger blocks, but also via horizontal scaling, which is usually called Ethereum Layer 2, which aims at millions of TPS. That first link also has more details in case you want to dive deeper.

Did the lightning payment network ever become popular?

As far as I am aware, it's barely used