Is Sharding really hard to implement?

Hi people

I was talking with crypto people on Twitter and some of the guys which I find them veterans tell me that Sharding is really hard thing to process and Ethereum will never make it.

I checked the roadmap and Ethereum delays Sharding 1-2 years.

Is it really that hard? Is Ethereum going to make it? How Sharding process is going and which phase are we at exactly?