I spent about a year looking for a job (senior management in cybersecurity), and had basically ZERO luck until I got wise and did the following. Had a new role within 4 months afterwards.

1. Take your resume, and expand it 10-20x into a massive document listing every single project, accomplishment, or skill you can think of that could ever be potentially relevant in a new role.
2. Every time you apply to a new job, copy the job posting into a ChatGPT conversation, and have it edit your resume to a 1-2 page document that only includes the experience most relevant to the job posting, and to rewrite sentences to use the exact terminology from the job posting where appropriate.
3. Once you have the custom resume, use ChatGPT to generate a custom cover letter to include as well.

These 2 changes will cause your resume to get assigned a higher "relevance score" by the AI tool their HR or recruiting team uses to weed through the 400+ applications they receive, which means you'll be at the top of the list of names that gets delivered to first human in the process (the recruiter).

You'll actually start getting callbacks and phone screens at that point, which gives you a fighting chance. The rest is up to you.

There are paid services that'll do this for you (like Teal), but you can do it yourself and with more control as long as you have access to ChatGPT. If you can generate a completely customized resume and cover letter in less than 2 minutes, you can pump out 10 high-quality applications in less than half an hour per day.

Edit: I see you're getting a 40% response rate. You may be setting your sights too low if that remains consistent. If you're applying for roles that are a solid step up form where you're at, you would expect closer to a 10% response rate.