A few sources I scanned seemed to believe the Arc 750 is a decent "budget" gpu, particularly at
1080p. Here is a comparison of the two you mentioned. UserBenchmark has kind of a lingering bad reputation for past biases in favor of Intel/NVIDIA but has since tried to turn that around.
I believe the rtx 2060 has 6 GB of vram, not 12. The Arc has 8 GB. Nowadays there's a huge debate on how much vram is acceptable in today's more complex games and most enthusiasts start at 16 GB. 8 GB is still within the middle bell curve, maybe for a 2-3 years, depending on what you use it for. It could be just fine for the rest of its natural life for your purposes.
What several sources cite as a downside are the drivers--described often as "buggy." Plus there was a recent disclosure "outing" Intel for enabling telemetry by default without notifying the user. There are other observations in various reviews I read. Here's one:
The Intel Arc A750 is a graphics card I want to love, but it's flaws are hard to ignore
www.techradar.com
The Arc 750 would be closely comparable to an rtx 3050 which is a low-end budget card with 8 GB of vram. Most advocate going to the rtx 3060/Ti w/8 GB each or the 4060Ti w/either 8 or 16 GB. Plus the drivers are way more mature than Intel's and the power requirements of 3060 vs 750 are slightly lower. The cost is about 100-150 USD higher though. The 4060Ti actually starts at 400 USD which is almost double the Arc's cost. Sorry, I don't have hands-on exp. w/AMD.
So, overall what I'm seeing is at best, the Arc 750 would be a minor upgrade over the 2060 based on vram and is very budget friendly--starting at around 220 USD.. But the driver thing would personally turn me off. And Intel has already stopped production of the Limited Edition Arc 770, which is never good news for a corporation looking to break into a very tough gpu market.