180 nm is what the first generation of Intel Pentium 4 and the second generation of AMD Athlon have used, in 2000.
While you would not want to make a CPU in 180 nm now, or any purely digital circuit, which could be better made with a FPGA, unless you need clock frequencies over 1 GHz, if you want to make any mixed digital-analog circuit with an important analog part, 180 nm can be fine.
Any analog circuit part made in 180 nm will not be much larger than in any up-to-date process, because the dimensions of the analog components are determined by functional requirements, such as noise or maximum current, not by the lithography limits.
While you would not want to make a CPU in 180 nm now, or any purely digital circuit, which could be better made with a FPGA, unless you need clock frequencies over 1 GHz, if you want to make any mixed digital-analog circuit with an important analog part, 180 nm can be fine.
Any analog circuit part made in 180 nm will not be much larger than in any up-to-date process, because the dimensions of the analog components are determined by functional requirements, such as noise or maximum current, not by the lithography limits.