The useful life of an ecommerce: 15-Year-Old ecommerce website

During the last year, organic visits have halved.

About half of the traffic goes to a blog, but blog readers do not transition to the ecommerce site. As soon as they read the article, they leave. Should the blog be removed, and a 301 redirect be set to the ecommerce site if there is no benefit to the store, other than irrelevant traffic for sales?

I suspect that the blog has been more harmful than beneficial for some time, but I would like to hear opinions and experiences on the matter.

Another topic that concerns me is the useful life of an ecommerce site. I see many shutting down, and it gives me the impression that when they reach a certain age, they lose relevance and decline in traffic. If you think about it, few brands last more than 6-8 years. Reviewing the graphs on Ahrefs, it seems to be a recurring trend. I have seen ecommerce sites that open another similar ecommerce and close the first one, but this strategy doesn't seem very clear to me. What do you think about it?

Thank you.