My mom was diagnosed with a form of aggressive kidney cancer about 10 years ago that had no really great treatments. Luckily it had not spread (apparently) and they cut out the whole kidney with good success. Until about 4 years ago when it returned, and it had spread to several places. She was going downhill so fast the changes were detectable day-by-day, but they started her on an immunotherapy combination that worked wonders. Gave her about 4 years, as it turns out, she finally succumbed to the cancer a few weeks ago. But it was an amazing four years! And that treatment did not exist when she was originally diagnosed. She'd have been dead years ago if they hadn't been able to buy her enough time for the treatment to become available.
Which is to say, I don't agree with your statement. Cancer treatment has made really great strides and continues to do so.