Are you talking about the Blizzard Crash Handler? (See image below)
This is a dialog form that collects a description of what your perception the game is in. Be as descriptive as possible including the game mode you were playing in, whether you are playing on live or on the PTR (obviously in this case the live client if it involves Competitive), what map, and what hero you are playing on. Don’t worry about system details as Blizzard collects relevant information automatically when that report is generated.
It is very important to copy that code that displays below the dialog, you can use that code in any web ticket for tech support and they can look up that crash log which helps them get a better idea of what the problem is.
Overwatch is not like any other Blizzard game and every game is unique from each other. I once was plagued with this dialog in season 2, crashing constantly. In the long run, it turned out to be the drivers for my USB headset of all things causing the crash. There are many possibilities to what can cause a video game to crash even if it seems only to be one specific game. Yes, there is a possibility it could be a problem with the game client, but more often than not it is specific computer builds or third-party software and drivers that can cause very problematic issues with the game client.
My error that I had back in Season 2 mostly occurred in Competitive, because I used voice comms in Comp more than other modes. More often most players commonly play one specific mode (Quick Play, Arcade, Competitive).
Every major patch there is always a spike of new players complaining about crashes (and this is true in almost every game, not just Overwatch). When game clients are updated, the general assumption is that they will be compatible with most systems that meet the recommended system requirements and for a high majority of the player base (we are talking a good 99% or more) this is true.
That being said there is always going to be exceptions and that is because computers will range so wildly. The Overwatch Development Team and the Blizzard Quality Assurance team do stress the client on a variety of systems ranging from those that barely meet minimum requirements (please try to not play Overwatch on such as system BTW) to the beefiest of machines. Even then there are problems. For example, the new RTX 2000 series of NVidia graphics cards were a plague for Overwatch (which is slowly being resolved by NVidia from what I understand; I don’t see as many RTX complaints these days), before that in 2017, the AMD Radeon graphics card drivers were causing widespread crashes on systems that tried to run the latest driver (this is long resolved), these are just two notorious examples that affected a larger portion of our community.
In short, is it Blizzard’s fault or the fault of the end user?
It’s a case by case basis. However, in most cases, it is my experience there is a technical malfunction or incompatibility that causes Overwatch to crash on most computer systems that are outside of Blizzard’s control or ability to resolve without assistance from the user.
So what can you do?
First, PLEASE stop playing Competitive until your issue is resolved. Unfortunately all disconnections and game crashes counts as leaving the match and will be penalized appropriately. The game server has no way to discern a legitimate disconnection or game crash from one that is forcefully caused by a dishonest player to bypass leaver penalties. You can learn about this policy here:
Secondly, get started on troubleshooting, a good basic step that may save a lot of time is to work through the standard Lock-up and Crashes for Overwatch troubleshooting guide (click here). Some of these steps are brain dead easy, some a little more complicated (especially those in the Advanced section), however a good majority of times many issues can at least be isolated if not resolved by following these steps.
There is a possibility more advanced help is needed, and there are two options. Start a web ticket or post in the technical support forum. Since you already crashed in a way that caused the Blizzard Crash Launcher to appear, Blizzard will already have a record of your crash. Just use the crash code number when you start a web ticket and Blizzard can look up possible causes to your crash more quickly. Posting in the technical support forum allows you to pool information with the community and get assistance from Forum MVPs, Blizzard Support Agents, and other members of the community.
In conclusion, crashes do suck and are infuriating, but if you really want to get to the root of the problem lets work to troubleshoot it carefully.