I am basically targeting SDE 3/SDE 2 roles. Would you say that I am being too overly ambitious?A lot of people were saying that I was not technically a senior software engineer even though my job title says that I am a senior software engineer. People have been saying that my impact hasn't been on the same level as a senior software engineer. Some people were saying that I didn't describe the impact I made in my resume. I am trying to understand if my impact has been not up to the mark or if its the way I framed my resume that's causing this problem.

My resume aside & my job title aside, I want to get some clarity on whether or not I can be considered a senior software engineer.

1. I have worked in 3 engineering teams so far. I switched out of each team voluntarily because I found a better opportunity. I was in the first team for 3 years. Second team for 1.5 years and I am currently in my second job/third team for around 1 year 2 months now.
2. In my first company, every junior engineer after he spends three years in the company automatically gets a senior software engineer title.
3. The second job that I got, I didn't apply for it. Every month I get atleast 10 recruiter mails on LinkedIn. The second job that I got was through LinkedIn. It was a Senior Software engineer job.
4. In this team and my previous team, I haven't had as significant of an impact as I had in my first team. This is because I haven't spent as much time in these two teams as I did in my first team. I am still ramping up. But even then I would say I have done some really nice projects in both of these teams. One of the projects that I did in my previous team was retiring these ids that we maintained in our team for incoming trades and using ids that were common across the whole company. As a part of this change, I got to clean up a lot of code paths. I got to eliminate a lot of unnecessary API calls. There was a lot of cache we held in memory because of these identifiers. I got to throw away all of that code and tidy up several of our systems. I think this is a senior software engineer project.
5. In the first team I was part of, I pitched an idea to my team lead to rewrite 20 year old shell/perl/awk scripts that we had for preprocessing data before we feed it into our system in Python. I spent close to a month studying those scripts. I came up with a very nice plugin architecture. The system could take multiple sources and the system would write output to multiple sinks. Both sources and sinks could be defined as plugins. Also as a part of this effort, I improved the performance of these scripts tremendously. We were making a lot of API calls for each files. I started batching up these API calls. I also started caching the results of these API calls in memory. These things allowed us to process files in 2 minutes flat. Previously it used to take over 75 minutes. Not only that. The people who wrote the original shell scripts are no longer with the company/no longer in this world. So every time we used to touch those scripts something used to break. When I touched these scripts, I broke things too. But after I was done, we added at least 3 more sources to my plugin based system and we did not cause any outages at all. I would consider this project a senior software engineer project too.
6. One of the commenters was saying that I because a senior software engineer after 3 years and I have to bring my A game to the interviews. I am not sure if he was implying that I became a senior software engineer too late or if I am became a senior software engineer too early? Either way, would you consider a software engineer with around 5.5 years of experience a senior software engineer?
7. As far as mentoring people goes, I wasn't ever assigned a mentee formally. But I have been helping junior engineers a lot. I am particularly knowledgeable about cmake/make and the general build process. On plenty of occasions I explained to junior engineers how static linking works and what dynamic linking is and how we are building an executable etc. Honestly having said that, I absolutely don't want to mentor people. I don't have the social skills for that kind of a task and I think every team lead I worked for so far has picked up on that too. That's why they never asked me to mentor anyone.

I am basically targetting SDE 3/SDE 2 roles. Would you say that I am being too overly ambitious?