It means you're not deemed a tax resident. However even some people living more than 180 days in Thailand will also not be Thai Tax Residents, depending on individual circumstances and DTAs
Bringing in cash and getting a local to exchange at an Forex booth is the only way to avoid tracking. Any WU, MoneyGram, Remitly transfer is easily tracked, as is card usage
Of course credit cards can be tracked. Any credit card charges in Thailand are cleared through one of the Thai banks. Your name, credit card number are retained on the clearing bank's database