Here are the problems with this post. First, you're not a 3.0 when it comes to playing ability. Of course, you've self-rated at 3.0 this year, but on movement alone, you're a low 3.5. Your actual playing record backs this up. Your league loss was to another self-rate who should be playing at low level 3.5 (and, as I predicted, he got worked by Larry Ladd). Your 3.0 tournament results, with the exception of the Colorado tournament, back up the idea that you should be rated at 3.5. I suspect had you played more than 2 USTA league matches, you would have been at risk of being DQ'ed and bumped up to 3.5 during the season.
Second, the Talk Tennis player you played is not a 4.5, and again, his playing results back that up (to be fair, he's likely much better than I am, so this shouldn't be construed as a shot at him; rather I want a discussion based in reality rather than subjective assessment). I couldn't find any league results for him, but he does have five tournament results in the last year. In 4.0 singles, he's 1-5. In 4.0 doubles, he's 3-2. In 4.5 singles, he's 0-2 (with three bagels in four sets). In Open singles, he's 0-1 (with one game won in two sets), and in Open doubles, he's 0-1 (with one game won in two sets). Nothing about those results say 4.5 singles player, though his 4.0 singles results show he's probably a mid-level 4.0 singles player (he rarely gets blown out and has lost some very competitive matches, so he might also be a higher than average 4.0).
So the matchup between you and him was a low 3.5 player and a mid-level 4.0 player. If you played a full best-of-three match, where players have time to adjust and compensate for that day's form, I'd have my money on him. If you played a single set, where "good" days and "bad" days can be magnified, I can see you taking the set off of him. As of yet, you have yet to tell us whether you beat him in a full match or some truncated version. I've seen plenty of matches where the lower ranked player hangs in for a set and then gets trounced in the next two, so I place little value in results that don't mimic a typical USTA league format.
And this is why people ITT continue to ask you for USTA-based evidence of both your rating and those of the people you best. The system, because of its foundation in actual match results, does a pretty damn good job of predicting match outcomes. Is it perfect? Not really, and especially so for new players who self-rate or those without a robust history of matches. You are an example of the former, and the system won't catch up to you until January 1st, when USTA Nevada gives you a 3.5 computer rating based on your tournament results.