Not really because most countries don't consider Bitcoin a currency. They consider it a commodity or an intangible and fungible asset. Yes, you can pay with intangible assets but it is not the same as with paying with US dollars. You can pay with your old socks if someone values them but it is not a currency (NB: I'm a big fan of Bitcoin, I'm just pointing out that from law and tax perspective it is NOT the same)
It doesn't need to be on a blockchain, that would be ridiculous︀ (after all e.g. some invoices are paid in cash with no proof of payment) -︁ it would be impossible e.g. due to exchange transactions, 2nd layer transactions, lightning network etc.︂ However, you should have some document proving that you really paid it. Most of the︃ time it won't be a problem but if it is a really large amount or︄ there is VAT and cross-country payments involved, you'd better have some document for it.
This is probably the biggest problem. You will put something︆ into expenses and you will have very little evidence of what it actually was and︇ whether you really paid for it. Some countries (think USA, Germany, Sweden...) are very strict︈ about this and they may not like it at all. In some countries it may︉ be acceptable (if you have e.g. invoice from the service provider saying the amount in︊ both USD and BTC).
You must remember that they do not have to prove you︋ are lying, it is actually the opposite. In many situations there is a "︌innocent until proven guilty" principle - e.g. you are accused of murder and the︍ police and prosecutor have to come up with evidence that you really did murder someone.︎ In tax-related situation if you get audited there is a "guilty until proven innocent️" principle unfortunately in many countries. The tax authority doesn't have to prove anything to you, you have to come up with documents and evidence. If you won't have them, you can go to court which can rule in their favour so you will pay extra taxes plus interest plus a fine. If it would be large amounts, it could be considered a fraud so it may not be only an administrative court but also a criminal court (both at the same time).
Of course I'm describing the worst possible situation. Your country probably won't "take away your freedom" as you describe because it is︀ in noone's interest. However if you will have very large expenses in Bitcoin without any︁ documentation, it may cause you an administrative hell in the future.