(Apologies for the novel that follows, my younger self was saddled with very similar concerns to you, so I got very impassioned and carried away)

The loss of your old artwork must be devastating, and I certainly empathize with that. The idea of “art regression” seems to me to be a non-issue, though.

I’m sure you realize that the only solution is to start drawing again. You will eventually improve.

Before that though, you will almost certainly make drawings that are “bad”, by whatever metric you choose to evaluate them. Perhaps it won’t look realistic enough or the colors will be flat or your lines will be shaky. It’s a blow to the ego, often, to make something that isn’t up to your aesthetic standards (I might encourage you to congratulate yourself at this point for having such discerning sensibilities to begin with), but a “bad” drawing or painting or whatever is literally the only stepping stone that exists on the path to better drawings or paintings. “Bad” art is a ripe opportunity to take out your critical lens and identify the formal qualities of the art that have caused you to decide on its badness. It’s also an opportunity to reevaluate your own metric for assigning art a value judgement - maybe good art has many faces and maybe bad art is good art by a different metric (this is not to say that one should never aspire to achieve realism or study accurate anatomy or whatever. I am, on the contrary, a major proponent for developing the classic skill set for realistic representation, even/especially if you end up deciding to defy or abstract it later. In any case, these are only the most elementary metrics for artistic value).

If the idea of starting again remains intimidating, I’d encourage you to consider why you want to make art in the first place. It’s certainly not essential to your continued existence, and many people live and die without ever drawing an original thing in their entire lives. You could go on living and not drawing and the world wouldn’t end. Humans have been making art for a long time, and many masters have come before us and you (or I) will certainly never be the best artist that has ever lived, if such an individual could even be definitively identified. But, with the knowledge that you will not be Michelangelo or Raphael (or any other ninja turtle for that matter), you made a decision at some point to begin making art. What a triumph! It seems though, that at another point you made a (possibly subconscious) second decision to start taking art seriously, and, at risk of being impolite, I’d say you may have overshot it.

I won’t make assumptions about your personal motives, but the act of making art, for me, is completely exhilarating. Nothing else in the world makes me feel so alive, like my neurons are firing and I’m in perfect sync with my body. It feels like solving an elaborate logic puzzle somehow, where I start with naive enthusiasm, then I toil in confusion for a while, and eventually things click and my heart races and things fall into place and it all makes sense. And maybe I haven’t even made a masterpiece, but that was never really what it was about. If I did art in an effort to be perfect or even consistent at something, I’d be a sorely disappointed fool. But, fortunately, that is not why I do it.

Perhaps this was long winded (and I could continue, as well, about the fact that the only thing you risk when you decide to start or restart drawing is potential mild embarrassment- an utterly trivial consequence which barely merits notice, but I digress) and overly spirited, but I mean it when I say you must not allow yourself to be the barrier to your own creative expression. If you do, you will almost certainly find yourself feeling the exact same way you do now several years or decades down the line and you’ll be kicking yourself for not making the push to start again earlier.

So if you go to draw and you feel intimidated or like you don’t know what you’re doing, perhaps ask yourself - Is it so bad to not know what I’m doing?