IIRC only 128K and larger require the newer Antic - with any modern day upgrade that uses SRam it shouldn't matter.
It depends on the type of DRAM, not on the amount of memory. The most 32 KBit (i.e. 41256) DRAMs and above need a minimum 8-bit refresh, but not all. On the other hand, also some 4164 DRAMs (64 KBit, Standard in XL/XE) needs the new ANTIC. For example, the Micron (MT...) DRAMs doesn´t work with old ANTIC, but the Hitachi 4864 and other do.
The biggest issue in this area is, that the normal user couldn´t realize instantly, that he _might_ be have a RAM failure. The ANTIC reduces refresh cycles when running without screen DMA or less display lines. That´s the reason why some demos, games and other programs, which switches screen DMA off during intialization or so on, doesn´t work with some DRAM and the old ANTIC. Also some sector copier programs writes garbage to disks, because they have to small screens and refresh isn´t enough for some DRAMs.
If somebody has an old ANTIC, it´s not a "no-go". Only use working DRAMs and test it with MEMDRV.COM or other RAM testers, which tests refresh.