How to stop DSolve from solving equations

It seems that Solve will be called during the DSolve calculation, so if you stop Solve, the DSolve doesn't work as well.

To avoid that, we can think in another way. Do not stop Solve, but store the equations whenever Solve is called. The last stored equations is what you need.

Here is a sample code, the usage of Block comes from What are some advanced uses for Block?

Unprotect[Solve];
Solve[args___ /; ! TrueQ[inF]] := Block[{inF = True}, Sow[args]; Solve[args]];
Protect[Solve];

Reap[DSolve[y'[x] == Sqrt[1 + (x/y[x])^2] - x/y[x], y[x], {x}]][[2, -1]]

(*{Log[1 - Sqrt[1 + y[x]^2/x^2]] == C[1] - Log[x]}*)

I do not know why the approach taken in the question does not work, because it depends on the inner workings of DSolve. However, this may provide the desired result.

Quiet@Block[{Integrate = Inactive@Integrate}, 
    DSolve[y'[x] == Sqrt[1 + (x/y[x])^2] - x/y[x], y[x], {x}]];
Activate[%[[1]] /. y[x] -> z[x] x] /. z[x] -> y[x]/x

(* -ArcTanh[Sqrt[1 + y[x]^2/x^2]] + 1/2 Log[-(y[x]^2/x^2)] == C[1] - Log[x] *)