While working on this PR https://github.com/bitcoin/bitcoin/pull/18570 I ran into a bit confusing situation where in one function a **CWallet reference** was expected while two others dealt with **CWallet pointers**. My initial reaction was: `let's harmonize them by making them references`. However, not being part of the PR itself I did't change anything and completed the PR first.

Now, after having analyzed the `rpcwallet.cpp` code I came to the conclusion that:

* converting them all into references is not the solution as they're originally **shared_ptr**s
* but also: there is no (visible) reason why every RPC function should begin like this:

```cpp
std::shared_ptr<CWallet> const pwallet = GetWalletForJSONRPCRequest(request);
const CWallet* const pwallet = wallet.get();
```

This clearly defeats the purpose of shared pointers for no obvious reason. *Maybe I am missing something?*

In my (unpublished) [code changes](https://github.com/brakmic/bitcoin/commit/0b3ee615491edf6f542631bf6ae6f72eac406550) all raw pointers got replaced with **shared_ptr**s but kept their original names (that is, *pwallet*). In the end, they're pointers too, so the most of the original code remained untouched.

However, some of the helper functions couldn't be changed because external code is accessing them and I didn't want to make this task "virulent". So I introduced new ("Ref") variants that expect **shared_ptr** parameters, namely: 

```cpp
void EnsureWalletRefIsUnlocked(const std::shared_ptr<CWallet>);
bool EnsureWalletRefIsAvailable(const std::shared_ptr<CWallet>, bool avoidException);
```

I have tested the code, with python and boost-tests, and could not find any errors. 
But before opening a PR I would like to open a discussion about this. 

Is there any reason to keep on working with raw pointers when every function call actually begins with *shared_ptr*s?

Regards,
if (scannedTime <= GetImportTimestamp(request, now) || results.at(i).exists("error")) {
                    response.push_back(results.at(i));
                } else {
                    UniValue result = UniValue(UniValue::VOBJ);
                    result.pushKV("success", UniValue(false));
                    result.pushKV(
                        "error",
                        JSONRPCError(
                            RPC_MISC_ERROR,
                            strprintf("Rescan failed for key with creation timestamp %d. There was an error reading a "
                                      "block from time %d, which is after or within %d seconds of key creation, and "
                                      "could contain transactions pertaining to the key. As a result, transactions "
                                      "and coins using this key may not appear in the wallet. This error could be "
                                      "caused by pruning or data corruption (see bitcoind log for details) and could "
                                      "be dealt with by downloading and rescanning the relevant blocks (see -reindex "
                                      "and -rescan options).",
                                GetImportTimestamp(request, now), scannedTime - TIMESTAMP_WINDOW - 1, TIMESTAMP_WINDOW)));
                    response.push_back(std::move(result));
                }
                ++i;
            }
        }
    }
    return response;
},
    };
}
static UniValue ProcessDescriptorImport(CWallet * const pwallet, const UniValue& data, const int64_t timestamp) EXCLUSIVE_LOCKS_REQUIRED(pwallet->cs_wallet)
{