Two questions:
1. If you arrive on a new passport, does the system link it to your old passport?
2. In the past year I have had 3 TV's (extended only 1 of the 3) and one 30 day exempt visa. If I arrive soon on another 30 day visa will I perhaps have a problem getting in? Would fly into BKK. (I am of age to be retired in LOS if that makes a difference)
I have tried to find previous posts with these questions .. to no avail.
TLDR : Answer Summary
The new passport will still be linked to your arrival and departure history based on personal details such as birth date, name, and country of origin. Even with a new passport, your prior entry history remains accessible to immigration authorities. Therefore, with your previous record of three tourist visas and one recent visa exemption, it's generally unlikely you will face issues re-entering Thailand on a new 30-day visa-exempt stamp.