Even though sensor technology has gotten better in 10 years, your old camera has two things your newer and cheaper cameras don't have: a bigger sensor and a brighter lens. So even though the new cameras have more resolution, they also require more noise suppression because of the less light those cameras capture. What you're seeing is the artifacts caused by the noise suppression. Bear in mind too that when introduced, the A2 was an $1100 camera. It likely had a much better optical quality lens than what is found in a current $250 camera.
So basically there is no free lunch. By moving to a more compact camera, you lost some performance. The only way to get it back is to use a camera with a bigger sensor and brighter and better quality lens. There are compact cameras that have those things, but they cost more.
I have a 10 year old Konica-Minolta Dimage A2 with a stated resolution of 8 MP. It takes beautiful pictures. I wanted something easier to carry around and obtained a Samsung TL220 compact camera with a stated resolution of 12 MP. I was unsatisfied with enlargements, finding them pixillated. I purchased a Sony WX150 compact camera with a stated resolution of 18.2 MP to replace it. I am still not satisfied with the resolution. What is going on?