@PMelkonian great question.
In my experience, creating a task in HubSpot as well does not guarantee a timely follow up, especially when this is a long term follow up with a “closed lost” deal. These are typically perceived as low probability by sales reps, who simply prioritize the recent and active communication. But I agree there is a huge potential to follow up on the communication, especially if it was not a hard NO as you mentioned.
To mitigate the fact that reps just don’t do it, we started developing Sellestial, the best follow-up system on top of HubSpot. We developed it to prevent missing any sales opportunities and make it super easy and effortless for the rep to stay on top of each and every one. Happy to chat over Zoom to see if that could also help you. Here is my scheduling link: https://meetings-eu1.hubspot.com/klemen-hrovat/meeting30
In your concrete case, did you think of creating a “fake” pipeline, where you would create a Lead deal for the one that is closed lost but matches the criteria you described? That way, you can keep your primary pipeline clean.
For us, I close lost deals, follow up with them, and if I manage to reengage them after, let’s say, 90 days, I would open a new deal. In that way, the sales cycle is more accurate.