Decentralized but needs ISP?

Alright so I’m generally a noob in the crypto space but i’ve been hearing this word decentralized a-lot and this question has been killing me. If you require your ISP to access the internet can we really call things truly decentralized? I feel as if thing get out of hand and government wants to block ethereum network access they could just do it at the ISP level no?

Side note: im a huge beginner with all this and sorry if this is a stupid question and it has already been answered or is extremely obvious.